Your daily forecasts from Boards.ie weather forum (NO CHAT)

Important: Please note legal disclaimer which can be seen at bottom of post 2565 dated 24 July 2012.

Tuesday, 20 November, 2012

Situation update: A fast-moving and rather limited disturbance is developing off the west coast and seems likely to produce an interval of strong winds. I have adjusted my schedule to keep a close watch on developments through mid-day, the alert at present covers a range of possible outcomes, guidance is not considered as reliable as usual given the volatile nature of the system. The most certain thing about it would be that it will not last very long however strong it becomes, a period of 2-4 hours of strong winds will move through, something like 1100-1500h on the west coast and 1300-1700h in parts of Ulster. Parts of the south and east will likely not see much increase in wind speed and will also miss the heavier showers.

ALERT for possible strong S-SW winds mid-day, accompanied by isolated squally showers with hail and thunder, situation remains somewhat uncertain, gusts to 80 km/hr seem probable and 120 km/hr possible as the system is expected to develop rapidly and have only a 2-3 hour duration moving through western and later northern counties ... some parts of south and east will not be affected ... there is also a squally frontal trough moving northeast towards inland Connacht and central Ulster that could give hail and torrential downpours ahead of the strong winds. Rainfalls generally 10-25 mm in regions outlined (much less in southeast).

ADVANCE ALERT for intervals of strong winds and heavy rainfalls Thursday and Friday, 20-40 mm rainfalls possible, rather windy on Thursday but gusts to 100 km/hr in SW winds developing on Friday.

Forecasts for Ireland

TODAY ... Breezy to windy with showers or periods of rain (further rainfalls of 15-25 mm in parts of Connacht, Ulster, 5-10 mm more common for south and east) with some hail and thunder, and highs near 10-12 C, southerly winds 40-70 km/hr may rise to 60-90 km/hr in the northwest mainly (higher gusts possible in exposed coastal locations) ... strongest winds likely around noon to 4 p.m. in coastal Connacht and 3 p.m. to 7 p.m. in west-central Ulster. These stronger winds may not make any impact on parts of south and east. A few squally showers will accompany the strong winds with hail and thunder, possible local tornadic wind streaks may develop (moving from southwest), a close watch will be kept, check for updates. Clare, Galway, Mayo, Donegal and nearby portions of other counties most at risk from this fast-moving event. While all this is happening, large sections of the south and east could be in relatively tranquil, partly cloudy to sunny weather at times.

TONIGHT ... Blustery in north at first, more moderate SW winds 30-50 km/hr elsewhere spreading to north by midnight, mild with a few showers in coastal regions mainly, lows about 6 C.

WEDNESDAY ... Breezy with winds SW 30-50 km/hr, showery and continued rather mild, some sunny intervals in east-central regions, and highs about 11 or 12 C, with a further 5-10 mm rain in some places.

THURSDAY ... Windy (S 50-80 km/hr) and mild with rain (10-20 mm), lows about 6 C and highs about 11 C.

FRIDAY ... Breezy to windy, SW 40-70 km/hr, some gusts to 90-100 km/hr by mid-day, showers or periods of rain, mild but becoming somewhat fresher. Winds SW 30-60 km/hr, lows near 6 C and highs near 10 C.

FURTHER OUTLOOK ... Weekend showery and a bit colder with squally showers at times, highs 7-9 C, overnight lows 2-5 C and a return to isolated and patchy frost and icy road sections.

Forecasts for Britain

TODAY ... Breezy mid-day with strong winds (80-120 km/hr) for Scotland and northwest England by evening, staying just breezy further south and east although rather windy in southwest and south central, S 40-70 km/hr. Showers including some hail and thunder. Very mild in south, highs 12-14 C. About 10 C in Scotland and northeast England.

TONIGHT ... Windy in Scotland, breezy elsewhere, mild, lows 5-8 C.

OUTLOOK ... Unsettled and breezy with showers most of the week, another period of strong winds likely for Scotland, northwest England, north Wales around Thursday. Highs remaining close to 10 C and largely frost-free nights. Slightly colder and staying unsettled on the weekend.


Forecasts for North America

Mild, dry weather dominates most of the U.S. with highs typically 10-12 C in the northeast states and Great Lakes, 15-18 C central plains and 20-23 C in the southwest and Gulf coast, Florida. Some rain at first near North Carolina coast but that system is heading out to sea now. Periods of rain in the Pacific northwest and southern B.C., mild into the southern prairies, snow across the northern prairies towards the western subarctic regions. Wintry cold has become firmly established "north of 60" with a blizzard raging in the far northern mainland and southern arctic islands in -15 to -25 C temperatures up that way. Down here in the "banana belt" we have had a misty and mild day with highs near 12 C and the overnight has become partly cloudy with occasional views of the half moon and (on the other side of the sky) Jupiter.

Watch for updates if we get better indications of potential for damaging wind gusts in western counties mid-day.

Important: Please note legal disclaimer which can be seen at bottom of post 2565 dated 24 July 2012.

Wednesday, 21 November, 2012

Forecasts for Ireland

TODAY ... Breezy and milder again by mid-day, any patchy frost should dissipate quickly as temperatures rise to about 8-11 C ... some sunny intervals with isolated showers at first, periods of rain developing from west to east later, 5-10 mm by evening ... winds rising to S 40-70 km/hr during the afternoon (some higher gusts possible near west coast).

TONIGHT ... Mild and showery with some steady rain at times, 10-15 mm rainfalls, winds S 30-50 km/hr with a brief interval of stronger winds possible (45-70 km/hr), lows 5-8 C.

THURSDAY ... Variable cloud with passing showers, breezy to windy at times, SW 40-70 km/hr and rainfalls 5-10 mm, except 10-20 mm parts of southeast as heavier rain develops there by later afternoon. Highs 9-11 C. Intervals of strong winds may develop (WSW 50-80 km/hr) by evening and overnight.

FRIDAY ... Breezy to windy, a bit fresher and cooler with passing showers, some with hail or thunder. Morning lows near 5 C and highs 8-10 C.

SATURDAY ... Partly cloudy, showers, rather chilly. Morning lows near 2 C and afternoon highs 7-9 C. Some patchy frost or black ice on roads in the morning.

SUNDAY ... Cloudy, periods of rain developing, risk of some strong winds depending on storm track (from south). Highs near 10 C.

OUTLOOK ... Models are converging on a colder pattern for the following week although I see hints that they may downgrade this closer to the time, so would not be too confident about any really wintry scenarios developing, probably just a bit cooler in a north to northeast flow and some frost at night, highs 5-7 C.


Forecasts for Britain

TODAY, TONIGHT and THURSDAY ... Frequently wet with strong southerly winds at times, about 30-40 mm rainfalls in total and highs both days near 10 or 11 C in south, 8-10 C in Scotland.

FRIDAY ... Windy with showers, a bit cooler, highs 8-10 C.

WEEKEND OUTLOOK ... Uncertain as to timing but showery at first, becoming windy and wet on Sunday, and slight risk of severe winds developing if the storm is both intense enough and tracks into Britain from Biscay. Another scenario brings the storm more towards Ireland. This would return Britain to a mild southerly flow until Monday.

FURTHER OUTLOOK ... Colder and possibly a bit on the wintry side in eastern regions, as the main thrust of colder air will be across the North Sea and into central Europe.

Forecasts for North America

Turning much colder across parts of the prairies with snow developing, temperatures falling to -10 C in Alberta (AB) and -5 C in Saskatchewan (SK), but mild in the eastern prairies and northern plains ahead of the storm, highs around 5-10 C. Wet at times on the west coast. Otherwise, large sections of eastern, central and southwestern U.S. and eastern Canada dry and mild trending to dry and very warm in the southwest. Highs about 12-14 C but nights rather chilly with patchy frost and fog in central and eastern regions away from the warmer Gulf coast region.

My local weather on Tuesday was quite variable with a few sunny breaks, passing showers and even some lightning observed off to the northeast where hail was reported. The highs were about 8 C.

Important: Please note legal disclaimer which can be seen at bottom of post 2565 dated 24 July 2012.

Thursday, 22 November, 2012

Forecasts for Ireland

TODAY ... Heavy rain should end soon in east, watch for leftover flooding in Meath, Kildare and Laois, also Louth and east Ulster. Strong wind gusts should also subside soon, but the day will remain rather blustery with variable cloud and further passing showers, winds SW 40-70 km/hr and additional rainfalls 5-15 mm. Highs 9-11 C. Intervals of strong winds may develop (WSW 50-80 km/hr) by evening and overnight and there could be another outbreak of thunder and lightning in a partial squall line around 3-6 p.m. Watch for updates.

TONIGHT ... Blustery, passing showers, 3-5 mm further rain, becoming a bit colder with lows 4-7 C. Winds decreasing later to WSW 30-50 km/hr.

FRIDAY ... Breezy to windy (WSW 40-60 km/hr), a bit fresher and cooler with passing showers, some with hail or thunder. Morning lows near 5 C and highs 8-10 C.

SATURDAY ... Partly cloudy, some sunny intervals but increasing high cloud, drizzle or light rain edging north onto south coast, rather chilly. Morning lows -1 to 3 C with patchy frost and icy roads, and afternoon highs 7-9 C. Rain and stronger winds arriving by evening.

SUNDAY ... Cloudy, periods of rain developing from early morning, risk of some strong winds, probably northeast backing to northwest, depending on storm track (from south). Highs 7 to 10 C. A rather raw day due to the wind and occasional rain.

MONDAY ... Further rain turning rather sleety over high ground, snow on summits, lows near 2 C and highs near 7 C.

OUTLOOK ... Rather cold most of next week in north to northeast winds, any precip could be mixed or sleety, widespread frosts at night, chilly days with highs 5-7 C. There is some chance of snow in the period although it does look somewhat marginal so far, away from higher elevations.


Forecasts for Britain

TODAY ... Showers heaviest in southwest Scotland, stormy over Irish Sea incl Isle of Man, north Wales, elsewhere, showers at times with strong southerly winds at times, about 20-30 mm rainfalls in total north, 5-15 mm south and highs near 12 or 13 C in south, 8-11 C in Scotland.

TONIGHT ... Windy with squally showers, lows 5-8 C.

FRIDAY ... Windy with showers, a bit cooler, highs 8-10 C.

WEEKEND OUTLOOK ... Some sunshine Saturday, showers more isolated in north then becoming windy and wet on Sunday, and risk of strong winds developing if the storm is both intense enough and tracks into Britain from Biscay. Highs near 10 C and some heavy rainfalls west and north.

FURTHER OUTLOOK ... Colder and possibly a bit on the wintry side in eastern regions, as the main thrust of colder air will be across the North Sea and into central Europe.

Forecasts for North America

In the U.S. where today is Thanksgiving Day, mild and sunny (13-15 C) across parts of the east and south central states ahead of a strong cold front with showers and a few storms developing west of Chicago to Kansas City, turning sharply colder in the northern plains states with light snow, snow ending further north and bitterly cold (-10 to -15 C). My local weather on Wednesday was cloudy with drizzle or light rain at times, highs near 11 C.

Important: Please note legal disclaimer which can be seen at bottom of post 2565 dated 24 July 2012.

Saturday, 24 November, 2012

Forecasts for Ireland

ALERT continues for icy roads this morning to about 1030h in more sheltered valleys. Watch for black ice conditions and poor visibility due to combined low sun angle and ground fog. A few places may see slippery roads again overnight especially north central counties.

TODAY ... Fog patches, frost slow to clear inland valleys, some sunny intervals away from south coast but increasing high cloud, drizzle or light rain edging north onto south coast mid-day, rather chilly for all regions. Temperatures near or below freezing in spots until 1030h, and highs 7-9 C. Rain and stronger winds arriving by evening in southeast.

TONIGHT ... Rain, gusty NE winds 30-60 km/hr across southeast, 5-15 mm mainly Wexford, Wicklow, Carlow, Waterford and south Kilkenny, possibly spreading to south Dublin. This rain will pull away before sunrise for most, and could turn to snow on higher slopes of Wicklow. Other regions partly cloudy and cold. Lows 4-7 C with the rain, and -2 to +3 C further north and west, some patchy ice on roads could develop inland north central valleys.

SUNDAY ... Cloudy with a bit of mid-day sunshine mainly for the north, periods of rain ending by morning in the east and southeast, possibly spreading into east Ulster for a time; winds northeast backing to northwest 40-60 km/hr, falling off mid-day before a further outbreak of rain across the south (mainly south of Limerick to Carlow) mid-afternoon to evening, winds once again becoming easterly at about 20-40 km/hr. Highs only 6 to 9 C making this a rather raw day due to the wind and occasional rain in the south. Risk of sleet or snow on higher terrain (sticking snow mainly near summit levels).

MONDAY ... Windy and cold, intervals of rain or hail turning rather sleety over high ground, snow possible in north above 400m, lows near 2 C and highs near 7 C. Winds NNW 40-70 km/hr making it feel sub-freezing where exposed to the wind.

TUESDAY ... Breezy and cold, isolated showers that may become mixed, lows near -3 C and highs near 6 C, winds N-NW 20-40 km/hr, somewhat greater chance of wintry showers in Connacht and west Ulster.

WEDNESDAY ... Variable cloud, isolated wintry showers, cold. Lows near -3 C and highs near 6 C. An interval of sleet or rain may develop in west towards evening lasting overnight.

THURSDAY ... Sleet or rain turning to wet snow, a bit milder in west at first, turning colder again later. Lows near 2 C and highs near 5 C.

FRIDAY-SUNDAY OUTLOOK ... This period is rather uncertain with a wide spread in the models, but expect cold weather to continue with perhaps a scattering of wintry showers in east to northeast winds. The less probable outcome would be a gradual return to somewhat milder weather, but I think this may take its time returning, perhaps around 3-5 December. At the same time, I don't think this will be too severe a wintry period ahead, although in a few places snow may settle briefly, and there will be widespread sharp frosts. Temperatures will be 4-6 degrees below normal for the period.

Forecasts for Britain

TODAY ... Some sunshine at first, then rain arriving mid-day southwest to evening Midlands-Wales, moderate southeast winds 30-50 km/hr, rain amounts about 10-20 mm, showers more isolated in north then becoming windy and wet by tonight. Highs 7-10 C.

TONIGHT ... Rain, strong SW veering NW winds 40-70 km/hr, lows near 5 C in south, 2-4 C Scotland.

SUNDAY ... Windy and colder, rain may turn to sleet or hail in places, highs about 7 C south to 4 C north.

FURTHER OUTLOOK ... Colder and possibly a bit on the wintry side in eastern regions, as the main thrust of colder air will be across the North Sea and into central Europe. Some snow could fall in the eastern counties of both Scotland and England as early as Monday and Tuesday, and also in higher parts of Wales but lower down there will be mixed showers at times. The average highs will range from 7 C in the southwest to 2 C in parts of the northeast and north. Frost will become frequent although it may stay too overcast with sleety precip so that icy roads may be more significant than frost.

Forecasts for North America

Windy and turning much colder in the northeast U.S. with showers coast, flurries inland; lake effect snow squalls in northwest winds near Great Lakes. Highs only -2 to +3 C inland to 4-7 C coast. Also rather cold further south although more sunshine and highs 7-10 C in blustery west to northwest winds. Trending to sub-freezing and then below -10 C in western Canada in this extensive arctic air mass that covers all but the western coastal margins of the continent and parts of far eastern Canada. Warm and dry in the southwest, trending to near normal further north along the coast ahead of a weak frontal trough that will bring in a modified portion of the cold air mass later today and overnight. My local weather on Friday was cloudy with light rain and highs 8-10 C.

UPDATE _ Sunday 25 November 2012 _ 6 p.m.
__________________________________________

Scattered areas of rain across the south and east will weaken gradually but some areas could see 5-10 mm further by midnight. Upper air soundings suggest that snow could fall on higher slopes of the Wicklow Mountains mainly above 500m before this system pulls away late tonight.

Although Monday and Tuesday will be generally dry and cold, a few areas appear prone to mixed wintry showers, notably Donegal, Derry, Sligo, Leitrim and Mayo in the northwest, and coastal Wicklow possibly up to south Dublin where "Irish Sea streamers" could brush the coast.

Precipitation in these showers will likely be mixtures of rain and hail near sea level, sleet about 150-300m above sea level, and snow above that, so there could be coatings of snow at times in higher elevations. However, we should stress that large portions of Ireland will remain dry as these showers will only be covering perhaps 10 per cent of the land mass and probably a smaller percentage of the population depending on how Dublin fares. What will be more widespread are both morning frost and icy road sections. There will also be quite a cold north wind in exposed locations.

Wednesday looks to be a mainly dry and cold day, then towards evening and overnight a frontal wave will attempt to push the colder air back and may succeed in bringing milder air into west Munster for a time but further north and east there could be a band of mixed precipitation lasting into part of Thursday.

From that point on, the "GFS" model is continuing to advertise a good potential for wintry weather but it seems that most of the other guidance has shifted back to a milder scenario so the more likely outcome by about next weekend would be a return to milder weather around 8-10 C with at least some rain. However, stay tuned because this model disagreement may only just be getting started.

UPDATE _ Tues 27 Nov 0530h

MTC is in transit and only has enough time to report that forecast is generally on the same course as earlier, with the note that the mixed precip event advertised for early Thursday may take most of Thursday now to develop.

I hope one of my regular helpers will update more comprehensively later today or perhaps I will get a chance. Have a great day.

Thanks, Wolfe, I am now in Ottawa where it is about a hundred degrees colder than in Vancouver (well not really, maybe ten). This has frozen my brain which I carry around in a jar since, well you know, so it is good to see a forecast already presented. I will resume normal service around 0900h Wed 28th, full moon by the way occurs tomorrow (14:47 UT or z or GMT, about at sunrise where I live and may in fact be by then. My buke says that we are to enjoy a penumbral eclipse which I guess means that the moon narrowly misses the umbra or shadow of the earth and turns a shade of slight red, if there would be clear skies at my home base on Wed morning I may stumble out to have a look (it would be 0647h so quite dark, but most likely to be overcast anyway) ... I don't have the data handy but would imagine that the moon then moves past Jupiter a few hours later as IIRC we pass Jupiter on 2-3 December or so. You will have a good view of that if skies are clear Wednesday night.

Could see Venus from window of plane even half an hour after sunrise this morning flying into Ottawa which is "colder than a blank blank" whatever you folks like to say, have heard a few different endings for that around the land, most of them having to do with odd parts of the anatomy of various beings. Apparently once upon a time pilots took evasive action thinking Venus was an oncoming aircraft (before dawn) which must have led to an interesting conversation at job performance review.

Important: Please note legal disclaimer which can be seen at bottom of post 2565 dated 24 July 2012.


Thursday, 29 November, 2012

Forecasts for Ireland

ALERT for icy or slippery roads in many parts of Ireland this morning, in particular west-central (mostly inland) with freezing fog, freezing drizzle or sleet producing slick road (and pavement) surfaces. These conditions may improve in some parts by afternoon but will return shortly after sunset.

TODAY ... Rain and somewhat milder on the west coast, 3-7 mm, south winds veering to westerly 20-40 km/hr then increasing to northwest 30-50 km/hr; highest temperatures 5-8 C near the coast ... freezing drizzle, sleet, and patchy freezing fog further inland covering large parts of west-central Ireland, as well as some parts of the east where the freezing fog will be more prevalent. Highest temperatures will be generally 3-5 C in other parts of Ireland away from the west coast but some inland valleys could stay even colder (near -1 C). If any sunshine develops it would be most likely in north and east, low cloud might partially obscure the sun. The combination of fog and ice with low sun angle can be very dangerous for driving. Amounts of actual precipitation away from the rain will be generally 2-4 mm at most. Some sleet and hill snow is possible but amounts will be slight.

TONIGHT ... Extensive freezing drizzle, freezing fog with lows -3 to -1 C, but somewhat milder near west and north coasts in a moderate NW wind. Patchy sleet or snow possible on higher terrain. Any locations that clear briefly could see lows of -5 C and dense freezing fog later towards sunrise.

FRIDAY ... Staying quite cold for most, but less widespread freezing drizzle or rain, just a brief interval of mixed precip for east Ulster towards evening, and patchy outbreaks of 1-2 mm drizzle with highs about 3-5 C on average, some valleys colder, and some coastal locations milder (to 8 C).

SATURDAY ... A cold and frosty start, freezing fog in valleys, lows -5 to -2 C then partly cloudy, a bit milder for most during the day, highs 6-9 C, although a few spots could stay colder where fog fails to clear ... some drizzle or mist near west coast by evening.

SUNDAY ... Another rather cold morning, but frost and ice dissipating fairly quickly, lows -3 to +2 C, then variable cloud, followed by periods of rain in a moderate southwest wind, highest temperatures of 7-10 C likely to occur during the evening or overnight.

MONDAY ... Milder and rather windy with showers, some heavy at times, rainfalls about 10-20 mm. Lows near 5 C and highs near 11 C. Winds WSW at 50-80 km/hr.

TUESDAY-WEDNESDAY ... Windy and rather mild, westerlies 70-100 km/hr at times, severe gusts may develop in Connacht and west Ulster ... highs around 9 or 10 C.

OUTLOOK ... A somewhat colder trend will develop in northwest winds and mixed showers could result, but highs will stay well above freezing at 5-7 C. Nights may once again become rather frosty with scattered ice and frost inland.

Forecasts for Britain

TODAY ... Mostly clear above any low-level cloud and fog, some sunshine will get through the murk, and a few sleety showers could fall in weak streamers coming inland from the North Sea in a moderate northerly flow. Highs about 4 to 6 C for most, colder in some valleys where dense fog fails to clear.

TONIGHT ... Clear intervals but widespread freezing fog, freezing drizzle and icy roads, lows -7 to -4 C away from somewhat warmer large cities (-2 C) and coasts.

FRIDAY ... Little change, partly to mostly cloudy with ice fog and some freezing drizzle at colder times of day and in some valleys mid-day, highs around 2-5 C.

OUTLOOK ... The cold spell will slowly fade out over the weekend although there will be considerable fog and mist, highs 5-7 C then next week's trend will be similar to the forecast above for Ireland, milder and windy at times.


Forecasts for North America

Large portions of the U.S. (excluding Alaska and Hawaii) are under the control of sprawling high pressure with temperatures trending from below normal (around 5-7 C for highs) in the east to near or above in the west, but Oregon and Washington along with B.C. are under cloud, rain and strong south to southwest winds. There are outbreaks of light snow across most of western Canada well north of the international border, 2-5 cm amounts and some freezing fog. A very weak frontal wave near Lake Michigan will spread light snow or freezing drizzle into the eastern Great Lakes and towards the inland northeast states later. My local weather on Wednesday has been damp to wet and mild with moderate south winds, high of about 7 C.

Astronomy note: Sorry about the disruptions to my forecast "blog" in recent days, the full moon came and went earlier at 14:47h Wed and the Moon has just moved past Jupiter as of 0100h today.

Important: Please note legal disclaimer which can be seen at bottom of post 2565 dated 24 July 2012.

Saturday, 1 December, 2012

Forecasts for Ireland

ALERT for icy or slippery roads in some parts of Ireland tonight, in particular north to east-central (mostly inland) with freezing fog producing slick road (and pavement) surfaces. These conditions will improve by about 10:00h, sooner towards the midwest as milder air moves in faster there.

TODAY ... Patchy freezing fog in valleys as morning temperatures stay around freezing, also some fog at temperatures above freezing becoming partly cloudy, a bit milder for most during the day, highs 6-9 C ... isolated drizzle or light mixed showers possible during the day.

TONIGHT ... Clear intervals east and north, cloudy south and west ... freezing fog may develop especially inland east and north, lows -3 to +2 C but milder south and west, lows 3-6 C, rain developing there.

SUNDAY ... Rain moving east may start as sleet or freezing drizzle further east mid-day, before milder air flushes all of the cold air out of valleys. Periods of rain giving 5-15 mm in a moderate southwest wind 30-60 km/hr, hill fog and snow on summits, for most lower elevations highest temperatures of 7-10 C likely to occur during the evening before falling back towards 2-3 C overnight into Monday. Winds veering westerly by evening, rain ending with partial clearing. It will feel very cold until late in the rainfall event as the cold air will take some time to scour out.

MONDAY ... Clear intervals early morning, some risk of freezing fog returning well inland, lows -1 to +3 C, but the day turning milder again, and rather windy with showers, some heavy at times with hail or thunder, rainfalls about 10-20 mm and highs 9-10 C. Winds rising late in day to reach WSW at 50-80 km/hr.

TUESDAY-WEDNESDAY ... Windy and feeling cold especially north, due to westerlies of 60-80 km/hr at times, strong gusts may develop in Connacht and west Ulster, elsewhere, winds 30-60 km/hr ... highs around 9 or 10 C Tuesday, 6-8 C Wednesday. Winds more northerly by end of period, mixed showers possible in north.

THURSDAY-FRIDAY ... Dry and chilly with frosts and some freezing fog returning, lows -3 to +2 C and highs 5-8 C each day. Some limited sunshine in a few western and southern inland areas.

OUTLOOK ... Somewhat milder conditions may follow towards the second week in December in a west to northwest anticyclonic type flow, and my research suggests it could get quite windy around the 12th-14th although the models have not picked up much on that at this time range.


Forecasts for Britain

TODAY ... Mostly cloudy, a few mixed or sleety showers but not much accumulation, some lingering fog and frost east-central inland. Cold with any weak sunshine not making much of an impact, highs 3-6 C.

TONIGHT ... Widespread fog and freezing fog, some freezing drizzle, lows about -5 to -2 C except milder in northwest with showers near coast.

SUNDAY ... Sleet or wet snow in some parts, turning to a steady rain late in the day, temperatures gradually rising to about 6-8 C by evening in a moderate southwest wind of 30-60 km/hr.

MONDAY-TUESDAY ... Windy, a bit milder, showers. Highs 8-10 C.

OUTLOOK ... Turning cold again mid-week, frost and fog returning.


Forecasts for North America

Cold and sunny (near -5 C) in parts of eastern Canada and New England, cloudy further south ahead of somewhat milder air reaching the Ohio valley and mid-Atlantic states during the day, bringing highs up to 8-10 C ... patchy snow across western Canada, heavier in parts of Alberta and central-northern B.C., mild with rain and fog near coast, highs there 10-12 C. Mild and dry for large sections of the south-central U.S., highs 18-21 C.

My local weather on Friday was mild with heavy rain at times, highs near 10 C and rainfalls of about 30-50 mm.

Important: Please note legal disclaimer which can be seen at bottom of post 2565 dated 24 July 2012.

Monday, 3 December, 2012

Forecasts for Ireland

MONDAY ... Becoming rather windy with any sunshine giving way to cloud and showers, some heavy at times with hail or thunder, rainfalls about 10-20 mm and highs 9-11 C. Winds rising late in day to reach WSW at 50-80 km/hr in exposed coastal locations, otherwise 40-60 km/hr.

TONIGHT ... Partly cloudy with a few more showers, some rather wintry on higher ground in the north, although some other places staying dry, lows about 2-5 C on average, with slight risk of isolated frost and icy roads most likely in higher parts of north.

TUESDAY ... Windy and turning colder (W to NW 40-70 km/hr, some higher gusts possible in northwest), squally showers may become mixed or wintry over higher parts of north. Highs 5-8 C mildest in southeast. Further rainfalls about 5-8 mm.

WEDNESDAY ... Cold and breezy with passing wintry showers in north, longer dry intervals elsewhere, some sunshine ... morning lows -2 to +3 C with some ice and frost, afternoon highs 5-8 C. Winds northerly 30-50 km/hr.

THURSDAY ... A cold start with widespread frost, risk of ice or freezing drizzle before milder air with rain arrives later in the day, winds increasing to westerly 50-80 km/hr. Morning lows -4 to -1 C and afternoon-evening highs about 8-10 C.

FRIDAY ... Windy with mixed wintry showers for some parts of north, cold rain or hail showers further south, winds NW 40-70 km/hr, temperatures steady in the range 4-6 C possibly falling below that in north.

SATURDAY-SUNDAY OUTLOOK ... At this point the weekend is looking rather cold in a continued unsettled northwest to northerly flow, highs near 5 C, and slight frosts with icy roads in the usual places overnight and morning. A very cold high may settle in during part of the week before milder air returns later but we should note that about a week ago, the models were over-estimating how strong the arctic air mass might become, so there's some chance that forecasts will back off to continual unsettled cool rather than cold weather. In the longer term, it seems to me that a spell of severe wintry weather is almost inevitable this winter, given how widespread below normal temperatures have become to the east, but I continue to think the best chance for this is later January and February. Cold spells this month might not be that deep or long-lasting although the month could average a bit below normal (although I have said elsewhere that I am expecting very mild weather for a few days around Christmas).


Forecasts for Britain

TODAY ... Windy, and milder than previous days especially for eastern sections, with frequent showers. Highs 8-10 C. Winds WSW 40-70 km/hr.

TONIGHT ... Breezy, milder than previous nights, lows 3-6 C. Showers and some hill fog.

TUESDAY ... Windy, squally showers, turning much colder late in day in Scotland and northern England. Highs before that 8-10 C. Winds W to NW at about 50-80 km/hr.

WEDNESDAY ... Windy and colder with mixed wintry showers, hill snow. Winds northerly 40-70 km/hr, highs 4-7 C.

THURDAY ... Cold and sunny to start, severe frost and some ice fog, morning lows around -5 C then intervals of snow, sleet or rain turning milder very late in the day and only west of the M6. Highs there 6-8 C but staying near 2-4 further east.

FRIDAY ... Windy with heavy showers, turning sleety as winds veer from west to northwest, snow on hills by late in the day. Highs 7-9 C early in south.

OUTLOOK ... See Ireland forecast, same general comments apply.


Forecasts for North America

Very mild now in all eastern and most central regions of the U.S. and adjacent southeast Canada with highs 12-16 C in the Great Lakes region and 16-20 C further south, ahead of areas of rain changing to sleet and snow near southern Manitoba and a heavy snowfall across the rest of the prairies today, in northeast winds of 50-80 km/hr and temperatures falling to -15C.

Heavy rain on the west coast with a new frontal wave approaching later today, foggy ahead of this, mild. Highs near 10 C. My local weather on Sunday was brighter than previous days although mostly cloudy, and rain was sporadic and rather light.

Important: Please note legal disclaimer which can be seen at bottom of post 2565 dated 24 July 2012.


Wednesday, 5 December, 2012

Forecasts for Ireland

ALERT for slippery or icy roads in some parts of northern and central Ireland until about 10:00h.

ADVANCE ALERT for the risk of severe wintry weather arriving around a week from today and lasting several days to a week. See discussion in outlook section of forecast.


TODAY ... Cold and breezy with passing wintry showers in north, longer dry intervals elsewhere, some long spells of sunshine ... some ice and frost will persist well into the morning in shaded areas with afternoon highs 5-8 C. Winds northerly 30-50 km/hr.

TONIGHT ... Clear to start in southeast, clouding over elsewhere, coldest around midnight (lows -3 to +2 C in south and east) but temperatures rising much of the night in west as rain arrives on southwest winds of 30-50 km/hr. This rain could start as sleet or wet snow in higher parts of inland south and east, but will be turning to rain before dawn in most parts.

THURSDAY ... Risk of icy roads from freezing drizzle or wet snow is most likely before dawn inland south and east, before milder air with rain arrives later in the morning, winds increasing to WSW 50-80 km/hr. Morning temperatures near 2 C east and 7 C west, then afternoon-evening highs in all regions about 8-10 C. Gale force gusts likely in Connacht and west Ulster towards evening with a wind shift to NW 40-70 km/hr.

THURSDAY NIGHT ... Windy and turning colder with squally showers becoming wintry over parts of the north. Lows 2-4 C.

FRIDAY ... Windy with mixed wintry showers for some parts of north, cold rain or hail showers further south, winds NW 40-70 km/hr, temperatures steady in the range 4-6 C possibly falling below that in north. There could be some accumulations of snow on hills in Donegal, Mayo and nearby counties.

SATURDAY ... Breezy and rather cold with mixed showers, some slight accumulations of sleet or snow on higher terrain, lows 1-3 C and highs 5-8 C.

SUNDAY ... Very cold to start with severe frost in some inland areas, lows about -5 to -2 C, then partly cloudy and somewhat milder by mid-day and afternoon in coastal districts at least, some inland locations could remain very cold with ice fog. Highs variable, near freezing inland, 7-10 C near some coasts (Dublin most likely about 4-6 C).

OUTLOOK ... Near normal temperatures may develop for a day or two early in the week with highs 5-7 C in a dry if foggy pattern, but much colder air is massing over the Baltic regions and will begin to make a westward push around Tuesday possibly overspreading most of Britain before arriving in Ireland with sub-freezing temperatures and the potential for snow mid-week, and this spell could last several days, a week or even longer. My speculation would be that this cold spell will break down in stages around the 23rd-24th leading to a milder spell Christmas Day to about the 28th with rain and strong winds possible then. Confidence in that is only moderate because this cold spell seems to be "on time" otherwise you'll very likely hear that this severe cold could intensify and dig in for a long time. I think it will come and go several times before a more severe spell later in the winter, so we'll see how that plays out, but in any case, best to be prepared for some intense cold and very likely widespread snowfalls at some point. The snow potential from current maps for around the 11th to 13th is significant but amounts are difficult to estimate this far in advance, don't be surprised if fairly heavy amounts start to appear in forecasts by the weekend. The eastern half of the country is more favoured at this point.


Forecasts for Britain

TODAY ... Windy and colder with mixed wintry showers, hill snow. Winds northerly 40-70 km/hr, highs mostly in the range 4-7 C (2-4 C east). Frequent wintry showers in northerly winds from North Sea, some accumulations of snow or sleet. Sunshine at times in west but squally local hail or snow showers coming off the Irish Sea in north Wales and further south into Somerset, Devon.

TONIGHT ... Generally clearing with wintry showers more isolated to east coast, sharp to severe frosts, lows -8 to -5 C. Some dangerous road conditions likely with freezing fog and icy sections.

THURSDAY ... Very cold to start, severe frost and some ice fog, some sunshine developing more likely near coasts, intervals of snow, sleet or rain turning milder very late in the day and only west of the M6. Highs there 6-8 C but staying near 2-4 further east. The milder air will reach the east by about midnight.

FRIDAY ... Windy with heavy showers, mildest around sunrise in a fast-moving warm sector but rain turning sleety as winds veer from west to northwest, snow on hills by late in the day. Highs 7-9 C early in south. Temperatures falling to 3-5 C by afternoon and evening. Blizzard-like conditions at higher elevations of Scotland and northwest England, Wales.

OUTLOOK ... See Ireland forecast, same general comments apply. Severe cold and some accumulating snow possible in eastern England around 10th-16th. If my research forecast is accurate, the Christmas holiday period could be a travel nightmare in parts of Britain especially northeast as milder air slowly pushes the cold air out with freezing rain or snow ahead of the warm fronts which may take days to push all the way across the region.


Forecasts for North America

Colder and quite breezy in the northeast U.S., snow squalls in the Great Lakes with highs near zero C. Cold and dry central states, sunny. Snow across the Canadian prairies again, -10 C and strong winds developing. Mild with showers on west coast but a drying trend developing as colder air filters south from central B.C. My local weather on Tuesday was variable with some places sunny, others under cloud with slow-moving showers, and widespread rainbows as a result. Highs were about 7 C.

Important: Please note legal disclaimer which can be seen at bottom of post 2565 dated 24 July 2012.


Friday, 7 December, 2012

Forecasts for Ireland


ALERT for slippery or icy roads in many rural and some higher urban areas tonight and repeating for the next few nights, as temperatures drop well below freezing, leading to freezing fog and frost.

ADVANCE ALERT continued for the risk of (moderately) severe wintry weather arriving around Tuesday night (11th-12th) and lasting several days towards the following weekend. See discussion for updated outlook.


TODAY ... Windy with mixed wintry showers for some parts of north, brief and isolatd rain or hail showers further south, winds NW 40-70 km/hr, temperatures steady in the range 4-6 C possibly falling below that in north. There could be some accumulations of snow (2-5 cm) on hills in Donegal, Mayo and nearby counties. Some parts of the south may have longer intervals of sunshine by afternoon. Frost could form this morning leading to some patchy ice on roads but conditions will probably be worse tonight.

TONIGHT ... Clear intervals, wintry showers confined to north, sharp frosts and icy roads developing in many rural areas, lows -5 to -2 C (about 2-4 C frost-free in some large urban areas and outer coastal locations).

SATURDAY ... Breezy and rather cold with mixed showers possible in north (only 1-3 mm potential), some slight accumulations of sleet or snow on higher terrain there, and highs 5-8 C. Further south, partly cloudy with a sharp frost inland, lows -3 to -1 C and highs 4-7 C except near 10 C southwest coast.

SUNDAY ... Very cold to start with severe frost in some inland areas, lows about -5 to -2 C, then partly cloudy and somewhat milder by mid-day and afternoon in coastal districts at least, some inland locations could remain very cold with ice fog. Highs variable, near freezing inland, 7-10 C near some coasts (Dublin most likely about 4-6 C). Widespread icy roads in morning hours.

MONDAY ... Partly cloudy, sharp frosts and light winds, lows near -4 C and highs 4-7 C. Some lingering ice fog may keep daytime readings near freezing in some inland valleys.

TUESDAY ... Mostly cloudy, misty (foggy over hills), sleet or wet snow developing east, cold rain west, in a northeast wind 30-50 km/hr, lows -2 to +2 C and highs 3-6 C.

WEDNESDAY ... Cloudy east, partly cloudy to sunny west, cold, isolated snow or hail showers in streamers near Irish Sea coasts and some parts of Donegal, Mayo. Winds generally NE 20-40 km/hr. Morning lows -5 to -2 C and daytime highs 0-4 C. Snowfall potential generally rather slight but with heavier amounts like 5-10 cms possible in a few cases (near if not actually in Dublin).

THURSDAY ... Partly to mostly cloudy, outbreaks of light snow mainly near east and south coasts, and in parts of northwest, 1-3 cms possible in most cases, and this could turn to sleet or rain near sea level. Lows -5 to -2 C and highs 0-5 C.

FRIDAY-SATURDAY ... Cloudy, sleet changing to rain at times in southwest, accumulating snow on hills, potential for some moderately heavy amounts, lows -3 to +2 C and highs 2-6 C.

OUTLOOK SUNDAY (16th) to CHRISTMAS DAY ... Starting today I will attempt to get a reading on the weather pattern before and during Christmas. Please bear in mind this time range requires more of a theoretical approach and so these outlooks are to be regarded as preliminary. The weekend of 15th-16th is likely to see a slight rise in temperatures and rain rather than snow especially by Sunday. The next few days are likely to be foggy and rather chilly as milder air moves in mostly aloft, highs from Sunday to mid-week are likely to remain 4-7 C. From about Friday 21st onward, a milder pattern is likely with south to southwest winds, strong at times, and rain on occasion including on Christmas Day. My prediction at present is for fog, rain and highs of 8-10 C on 25th-26th, windy on 27th-28th with further rain and possibly a colder turn.


Forecasts for Britain

TODAY ... Windy with heavy showers moving rapidly south through London and Thames valley this morning, clearing south coast mid-day, thus it will be mildest around sunrise (Midlands, Wales) in a fast-moving warm sector but rain turning sleety with some heavy wet snow squalls as winds veer from west to northwest or north at 50-80 km/hr, snow likely to accumulate on hills by late in the day. Highs 7-9 C early in south. Temperatures falling to 3-5 C by afternoon and evening. Blizzard-like conditions at higher elevations of Scotland and northwest England, Wales. Some sunshine will develop later in areas not in the path of sea-effect wintry showers.

TONIGHT ... Windy and cold with mixed rain and wet snow showers becoming more confined to southeast and North Sea coasts after midnight, slight frosts developing inland (west-central) with lows -2 to +4 C.

SATURDAY ... Partly cloudy to start in south, cold, as mixed wintry showers move into north, then central regions in a moderate westerly, partly cloudy with localized freezing fog and icy roads south-central, mildest near southwest coast where highs 8-10 C. Otherwise highs about 4-6 C with some places staying colder due to fog.

SUNDAY ... Wintry showers ending, scattered fog or ice fog and cold, highs about 3-5 C.

OUTLOOK ... See Ireland forecast from Monday on, same general comments apply, although colder air arrives in northeast during Tuesday. Severe cold and some accumulating snow possible in eastern England around 11th-16th. Stormy breakdown of cold spell could lead to a nasty mix of heavy snow, freezing rain, flooding rains into parts of the southwest, and travel disruptions on several days, then possibly the Christmas holiday period could continue to be a travel nightmare in parts of Britain especially northeast as milder air slowly pushes the cold air out with freezing rain or snow ahead of the warm fronts which may take days to push all the way across the region.


Forecasts for North America

Northeast states cloudy with patchy light rain developing, highs about 7-9 C. Some parts of inland southeast dry and mild, 12-15 C but rain near Carolina-Georgia coasts will merge with the Ohio valley rain over the northeast by tonight or tomorrow morning. Warm and dry in parts of the southwest, outbreaks of light snow northern Rockies into western Canada. Sleet or wet snow showers on west coast north of Oregon with highs at sea level near 5 and mainly below freezing inland with heavy snow in some mountain areas.

My local weather on Thursday was cloudy with some clearing towards evening, chilly, also a few light sleety showers, highs about 7 C.

Important: Please note legal disclaimer which can be seen at bottom of post 2565 dated 24 July 2012.


Sunday, 9 December, 2012

Forecasts for Ireland

Discussion: In the past day or so, the forecasting models have first shown a rapid breakdown of the cold spell mid-week, but now are showing a very gradual breakdown that is more in line with the forecast issued here yesterday morning. This may be confusing to readers and I apologize on behalf of the models who cannot in any case take the stand, although I feel like more of a victim than a perpetrator in this situation, to be honest I think we need to take the period Thursday to Saturday and review different possible outcomes and not treat any of them with a lot of confidence because there are probably three ways this situation can now "break down" so I will review those in the outlook. I do feel relatively confident of what's in the forecast to mid-week and I would put the most faith in the slow breakdown and eventual windy scenario. The other issue that requires comment is that it has remained much milder overnight than expected in the south, this is because the cloud and mild air associated with the weak low has spread over the whole country and prevented frost from forming. This will probably not have much effect on how things evolve past mid-day.


TODAY ... Mostly cloudy, rather mild with drizzly showers mostly in Leinster and east Ulster this morning, amounts slight (trace to 2 mm), highs 8-10 C. Winds rather light but veering slowly from NW to N 15-30 km/hr.

TONIGHT ... Partly cloudy to clear, turning a bit colder again, some isolated frost and icy road sections possible inland north and east, lows -2 to +3 C but could remain 3-6 C in west Muinster and even some parts of south Leinster.

MONDAY ... Partly cloudy, highs 5-8 C. Some lingering ice fog may give icy roads in the morning inland northeast, this should clear for a time, but falling temperatures shortly after sunset will bring back more extensive icy road conditions spreading almost to the west and south coasts by midnight or so.

TUESDAY ... Clear to start in many areas, then increasing cloud, becoming misty (foggy over hills), rain, sleet or wet snow developing east, cold rain west, in a northeast wind 30-50 km/hr, lows -2 to +2 C and highs 3-6 C. Slight risk of snow streamers developing locally near Dublin.

WEDNESDAY ... Cloudy east, partly cloudy to sunny west, cold, isolated snow or hail showers in streamers near Irish Sea coasts and some parts of Donegal, Mayo. Winds generally ENE 15-30 km/hr. Morning lows -5 to -2 C and daytime highs 1-6 C. Snowfall potential generally rather slight but with heavier amounts like 3-6 cms possible in a few cases (near if not actually in Dublin). Some areas inland could remain calm and foggy with lingering frost and icy roads. West coast on the other hand could turn milder by evening as winds from the south push slowly inland with drizzle and fog. Wednesday night could see sleet or wet snow in parts of northeast and east coast.

THURSDAY ... Partly to mostly cloudy, outbreaks of light snow turning to sleet and rain, mainly near east and south coasts, and in parts of northwest, 1-3 cms possible in most cases, and this could turn to sleet or rain near sea level. Lows -2 to +2 C and highs 2-5 C. For west Munster and some parts of Connacht, cloudy and turning milder in stages, with light rain, moderate south winds, lows near 2 C and highs near 6 or 7 C.

OUTLOOK ... The forecast becomes rather uncertain around Thursday and the above is my preferred solution, but it could also turn much milder rather quickly (8-10 C, rain) or it could stay stubbornly cold with snow mixing in more extensively especially across the north. The uncertainty is due to a developing frontal boundary that could lie just south of Ireland to about Ulster to north Wales. Much depends on where this sets up. Then, the uncertainty deepens because this frontal boundary could take all day Friday to move through Ireland, and during that time, a low could develop near Ireland and bring in either strong winds (south more likely to see this) or heavy mixed precipitation (north most likely). It's a bit of a forecasting nightmare at 4-5 days, so the best course to take (I believe) is to state the range of possible outcomes and say that I feel like the guidance is mostly converging on the slow breakdown with mixed wintry precip in the north and east, a cold rain in the west and south (snow on hills), winds slowly veering ESE to SSW and a moderate chance of a windy outcome too. If it does become windy, bear in mind that a perigeean new moon on 13th (09h) would bring higher than normal tides into the equation.

The breakdown scenario is likely to be moving into a westerly unsettled pattern no later than Saturday and from then on, we will resume the outlook countdown towards Christmas as per yesterday's outlook. Following is the preferred but by no means "carved in stone" outlook by days:

FRIDAY ... Cloudy with periods of rain and strong SW winds (50-80 km/hr) developing near south coast, highs 7-9 C but possible mixed rain and snow further north in continued east to southeast winds and temperatures only slowly edging up 2-5 C. Some risk of a more intense windstorm event, watch for updates.

SATURDAY ... Variable cloud, windy at times, showers, highs 8-10 C.

SUNDAY ... Showers or periods of rain with potential for another interval of strong to severe winds from SW to W, highs near 10 C.

OUTLOOK MONDAY (17th) to CHRISTMAS DAY ... The first half of the week is likely to be breezy to windy and continued mild (8-10 C), and there could be severe winds at some point during the mid-week, then there should be some more settled weather later in the week towards weekend 22nd-23rd with near-normal temperatures. From then on, a milder pattern is likely with south to southwest winds, strong at times, and rain on occasion including on Christmas Day. My prediction at present is for fog, rain and highs of 8-10 C on 25th-26th, windy on 27th-28th with further rain and possibly a colder turn.


Forecasts for Britain

TODAY ... Wintry showers ending in Scotland, Wales and northern England, and becoming less frequent in southern England in moderate northerly winds, cold east (4-6 C) but somewhat milder west with highs about 6-9 C. Some parts of northeast England and central Scotland could have persistent low cloud or fog and icy roads at higher elevations.

OUTLOOK ... See Ireland forecast from Monday on, same general comments apply, although colder air arrives in northeast during Tuesday. Severe cold and some accumulating snow possible in eastern England around 11th-13th. Stormy breakdown of cold spell could lead to a nasty mix of heavy snow, freezing rain, flooding rains into parts of the southwest, and travel disruptions on several days, culminating in heavy snow in Scotland and depending on how slow the breakdown develops, northern England too, heavy rain or mixed precipitation elsewhere and strong to severe winds in parts of the south on Friday 14th, possibly repeating on Sunday 16th with little respite between storms. Ferry schedules could be disrupted around this three-day interval, especially towards France. Most of the following week will be unsettled and windy, but well above freezing in most places, then possibly the Christmas holiday period could also be a travel nightmare in parts of Britain especially northeast as milder air slowly pushes cold air that may push in around 22nd-23rd out with freezing rain or snow ahead of the warm fronts which may take days to push all the way across the region.


Forecasts for North America

Widespread rain and fog in the northeast states, very mild air will push about as far north as Baltimore and Atlantic City, north of that east winds and about 8-10 C, south will see 15-20 C and chance of thunder with the more showery rainfalls. This system is rather sluggish and has only moderate winds, turning to northeast across the lower Great Lakes and Midwest where the rain will become sleety and end as wet snow in most places (ending tomorrow rather than later today). Cold and dry air has pushed into most of western Canada but extensive light snow has now broken out in the northern plains states with 5-15 cm accumulations and moderate northerly winds, falling temperatures. This pushes about as far south as Kansas and northern Missouri, south of that the weather is cloudy and seasonable (8-12 C). Dry and cool on the west coast with slight frosts.

My local weather on Saturday was cloudy with patches of blue sky and rather cold, highs of only 4 C. Very light showers at times were mixed rain and soft hail with snow falling on local hills.

Important: Please note legal disclaimer which can be seen at bottom of post 2565 dated 24 July 2012.

Tuesday, 11 December, 2012

Forecasts for Ireland

ALERT for widespread icy roads especially where untreated and near sources of water vapour like ponds and rivers -- also severe cold near -5C in some inland regions this morning, and in some cases this may persist in modified form most of the day. The southwest will escape the harsh conditions due to cloud cover.

Discussion: There seems to be a daily cycle where the models allow milder air in faster during the mid-day runs, then back off a bit for these morning runs. Also I am very suspicious about easy warming of dense slugs of arctic high pressure even near the Atlantic Ocean, so this is probably going to sound a bit colder than other forecasts at least to Friday mid-day, this is mostly because I have the belief that the cold air is going to prove stubborn and winds will take more of an easterly turn in the first stages of the transition to milder weather; this of course does not mean that subtropical Kerry will also stay cold, so if you want to escape the wintry feel, book in somewhere near the southwest coast.

TODAY ... Clear to start in many areas with icy road stretches on untreated surfaces, with low cloud from ice fog in valleys and near ponds or lakes, then after some clearing, increasing cloud, becoming misty (foggy over hills), patchy rain, sleet or wet snow developing east, cold rain west, in a northeast wind 20-40 km/hr, highs 3-6 C. Some places could remain fogged in and very cold (-1 C) prolonging the icy road conditions locally. Slight risk of snow streamers developing locally near Dublin, limited extent and inland fetch with these. Dry (except for the ice fog) and cold for many inland regions, lingering ice and frost, also some sunshine ... cloudy near west coast, some light rain at times, highs 6-8 C in southeast winds 20-40 km/hr.

TONIGHT ... Severe cold will redevelop in north Leinster and east Ulster, possibly some parts of north Connacht, but it may be somewhat less cold inland southeast and south under cloud, lows -4 to -1 C north, -2 to +3 C south. A few intervals of sleet or wet snow possible, with rain in southwest, just 2-5 mm amounts at most.

WEDNESDAY ... Cloudy east, partly cloudy to sunny west, cold, isolated snow or hail showers in streamers near Irish Sea coasts. Winds generally ESE 15-30 km/hr. Morning lows -5 to -2 C and daytime highs 1-6 C. Snowfall potential generally rather slight but with heavier amounts like 3-6 cms possible in a few cases (near if not actually in Dublin). Some areas inland could remain calm and foggy with lingering frost and icy roads. West coast on the other hand could turn milder by afternoon as winds from the south push slowly inland with drizzle and fog, highs 7-9 C. Wednesday night could see sleet or wet snow in parts of northeast and east coast.

THURSDAY ... Partly to mostly cloudy, outbreaks of light snow turning to sleet and rain, mainly near east and south coasts, and in parts of northwest, 1-3 cms possible in most cases, and this could turn to sleet or rain near sea level. Lows -2 to +2 C and highs 2-5 C. For west Munster and some parts of Connacht, cloudy and turning milder in stages, with light rain, moderate south winds, lows near 2 C and highs near 6 or 7 C. Potential for 10-20 mm rain in southwest and west, 5-10 mm mixed precip further east (3-7 cm snow on some hills).

FRIDAY ... This is still a balance of several different possible outcomes, if low pressure moves further noth, there could be extensive strong winds from the southwest, and also the snow potential mentioned here could be greater if the low tracks near the south coast. The forecast assumes a track across north-central Ireland. ... Cloudy with periods of rain and strong SW winds (50-80 km/hr) developing near south coast, highs 7-9 C but possible mixed rain and snow further north in continued east to southeast winds and temperatures only slowly edging up 2-5 C. There is a risk of very strong winds developing near south coast especially, and this applies also to Friday night into Saturday, as different guidance shows us different timing on a fairly strong low pressure system. where that does develop, coasts are also prone to unusually high tides due to new moon at perigee on Thursday.

SATURDAY ... Variable cloud, windy at times and possibly stormy, SW gales may develop Friday night into Saturday, showers or periods of rain and some risk of heavy rain 20-30 mm, highs 8-10 C.

SUNDAY ... Showers or periods of rain, breezy to windy SW to W, highs near 9 or 10 C.

OUTLOOK MONDAY (17th) to CHRISTMAS DAY ... The first half of the week is likely to be breezy to windy and continued mild (8-10 C), in fact there could be a strong windstorm around Tuesday, then there should be some more settled weather later in the week towards weekend 22nd-23rd with near-normal temperatures with some risk of a colder spell for a couple of days. From then on, a milder pattern is likely with south to southwest winds returning, strong at times, and rain on occasion including on Christmas Day. My prediction continues to be fog, rain and highs of 8-10 C on 25th-26th, windy on 27th-28th with further rain and possibly a colder turn before New Years.


Forecasts for Britain

TODAY ... Some inland locations staying very cold, near or below freezing with ice fog and slippery roads, otherwise cold (3-5 C) with variable cloud, some sun, some light flurries in east mostly. Winds light and variable in most of Scotland and northern England, trending to NE 20-40 km/hr in Wales and central England and 30-60 km/hr in southeast England, adding quite a chill in London and southeast coast.

TONIGHT ... Clear intervals, ice fog, very cold for most, cloud and a bit milder in the southwest with patchy rain turning to sleet or snow further north as it slowly moves in, heavy snow possible over hilly areas of southwest. Lows of about -7 to -10 C will be widespread, trending to about -2 C in southwest inland and 3-5 C southwest Cornwall.

OUTLOOK ... The breakdown will be a bit slower than discussed for Ireland, in most parts of Britain, except perhaps Cornwall and Devon ... snow or sleet may become fairly widespread with rain pushing slowly into southwest and only at lower elevations, so heavy snow possible on hills in Wales and Devon-Somerset. By about Friday, turning windy across the south, rain reaching the Midlands and east Anglia, snow or sleet, some ice in north-central regions. From about Saturday on, about the same forecast as above for Ireland.

Forecasts for North America

Rain turning to wet snow inland northeast, snow or sleet lower Great Lakes and Ohio valley, but staying rather mild with light rain at times Boston, New York and Washington DC (15 C). The trend to colder weather will set in there tonight. Otherwise, not much change from yesterday, very cold across much of the north-central U.S. and western Canada as snow moves into the western Great Lakes region. Showers near the west coast turning to wet snow above 500m inland.

My local weather on Monday was cloudy and somewhat foggy with highs near 7 C.

Important: Please note legal disclaimer which can be seen at bottom of post 2565 dated 24 July 2012.

Thursday, 13 December, 2012

Astronomy note: New moon occurs today at 0843h.

Forecasts for Ireland

ALERT for heavy rainfalls 20-30 mm in most regions and strong winds south and east coasts tonight into Friday morning.

TODAY ... Partly to mostly cloudy, a dry start for most with outbreaks of very light snow or sleet turning back to rain, mainly near east coast, and in parts of northwest, 1-3 cms possible on higher terrain, daytime highs 3-7 C except 8-10 C in west Munster and some parts of south Connacht, where it will be cloudy and turning milder in stages, with light rain, moderate south winds. Strong winds arriving in southwest around sunset.

TONIGHT ... Rain with some thunder possible, arriving in southwest and west early evening, 5-10 mm mixed precip further east around midnight (2-5 cm snow on some hills, sleet then rain lower down). Becoming very windy across the south and southwest by evening, winds increasing to SE 50-80 km/hr, very high tides likely with some minor coastal flooding. This rain and wind storm will continue through the night giving 20-30 mm rain and strong gusts moving rapidly through the south and up the east coast later, ahead of milder air; when that arrives, winds will veer rapidly SW and decrease to SW 40-60 km/hr.

FRIDAY ... Strong winds and heavy rainfalls moving through east and north during morning hours, as variable cloud, showers and milder southwest winds reach other regions. Overnight temperatures rising to 6 C across the south, some pockets of colder air trapped in east Ulster 2-4 C may persist as the stronger winds are swept away into Britain. The rest of Friday will become partly to mostly cloudy with showers or periods of rain, a further 10-20 mm with SW winds 40-70 km/hr, highs 8-11 C south and 4-8 C north.

SATURDAY ... Variable cloud, windy at times and possibly stormy, rather strong SW winds near west coast 50-80 km/hr, otherwise 30-60 km/hr, showers or periods of rain and some risk of heavy rain 20-30 mm, morning lows 2-5 C, highs about 8-10 C south, 5-8 C north.

SUNDAY ... Showers or periods of rain, breezy to windy SW to W at 40-70 km/hr, morning lows 3-5 C, highs near 9 or 10 C.

MONDAY ... Cloudy, light rain or showers, some sleet or melting wet snow possible on hills in northwest, a bit colder in west to northwest winds 30-50 km/hr, lows of 1-3 C and highs around 7 C.

TUESDAY ... Frosty start, dry and partly cloudy daytime, lows -2 to +2 C and highs 6-9 C.

WEDNESDAY ... Windy, periods of rain that could start as sleet in north, milder in stages, lows 0-3 C and highs 7-11 C.

OUTLOOK THURSDAY (20th) to CHRISTMAS DAY ... Unsettled late in the week into Saturday 22nd, then a brief colder and dry spell around Sunday 23rd with slight frosts, followed by milder and breezy to windy conditions by Christmas Eve and Christmas Day, becoming windy or even stormy by 26th and 27th, highs during the holiday period near 10 C in strong southwest to west winds. There could then be a colder turn before New Years.


Forecasts for Britain

TODAY ... A very cold start except in southwest, with ice fog lifting mid-day to reveal variable cloud cover then some outbreaks of sleet and light snow, in a keen southeast wind as temperatures rise slowly to 1-3 C (5-8 C southwest). This sleet will change to rain from south to about Midlands during the evening hours but then heavier sleet or snow may develop in north-central England, higher elevations of Wales, and into southern Scotland.

TONIGHT ... Stormy across the south with gale force SE winds, heavy rainfalls, thunder late ... rain mixed with snow further north, some heavy snowfalls possible in northeast England and southern Scotland in gale force ESE winds. Temperatures rising through the night to reach 8-10 C south and about 3-5 C in southern Scotland.

FRIDAY ... Windy and milder, some strong gusts across the south from a west to southwest direction, rain becoming showery. Highs 8-10 south, 3-5 C north with strong east to southeast winds.

OUTLOOK ... Similar pattern to Ireland from weekend on, mostly rather mild with frequent showers, also a similar outlook for Christmas period.

Forecasts for North America

Most parts of the U.S. will be dry with just southern California and southern Nevada seeing some showers, but this will eventually set off light snow further north at higher elevations of the Great Basin region. That will continue into the central plains states on Friday. Meanwhile, cool and dry for most of the east with a remnant of yesterday's rain pulling away from the Carolina coasts. Mild and dry in the south central states into the desert southwest until west of Phoenix AZ with the Pacific moisture setting off late showers. Heavier rain will move onto the BC and WA coasts mid-day making gradual inland progress turning to snow in the Cascades. It remains cold across most of western Canada with a light snowfall moving through the Great Lakes mostly on the Canadian side but some falling in Michigan's upper peninsula.

My local weather on Wednesday was dry but cloudy, high near 6 C.

Important: Please note legal disclaimer which can be seen at bottom of post 2565 dated 24 July 2012.


Saturday, 15 December, 2012

Forecasts for Ireland

TODAY ... Partly to mostly cloudy, windy at times, with rather strong SW winds near west coast increasing to 40-70 km/hr, otherwise 30-50 km/hr, showers or periods of rain with generally 5-15 mm, highs about 8-10 C south, 5-8 C north.

TONIGHT ... Cloudy, showers or periods of light rain, lows 3-5 C. Winds backing to southerly 15-30 km/hr. Rainfalls 3-5 mm.

SUNDAY ... Frequent showers or periods of rain, breezy to windy SW to W at 40-70 km/hr, morning lows 3-5 C, highs near 9 or 10 C. Rainfalls about 10 mm.

MONDAY ... Cloudy, light rain or showers, some sleet or melting wet snow possible on hills in northwest, a bit colder in west to northwest winds 30-50 km/hr, lows of 1-3 C and highs around 7 C.

TUESDAY ... Frosty start, dry and partly cloudy daytime, lows -2 to +2 C and highs 6-9 C.

WEDNESDAY ... Windy (SE to SSW 40-70 km/hr), periods of rain that could start as sleet in north, milder in stages, lows 0-3 C and highs 7-11 C south, 4-7 C north.

THURSDAY ... Showers, windy (SW 40-60 km/hr), lows 2-4 C and highs 6-8 C.

FRIDAY ... Variable cloud, isolated showers, lows 2-4 C and highs 6-8 C.

OUTLOOK SATURDAY (22nd) to Post-CHRISTMAS DAY ... Yet another Atlantic low arrives later Saturday 22nd into Sunday 23rd with wind and rain (possibly sleet in some northern regions), then after a brief colder and dry spell around night of Sunday 23rd and morning of Monday 24th with slight frosts, more rain and fog by Christmas eve, possibly mixing with sleet in north, a suggestion of a brief colder turn for Christmas night but then getting quite windy later into overnight St Stephen's Day into 27th as deep low pressure tracks slowly east across regions just north of Ireland, highs each day in this pattern about 6-8 C for most, 8-10 C southwest, but there is some range of possible outcomes that includes a milder solution as well as a colder one that would perhaps bring about the rather faint hope of a white Christmas in this pattern -- the one thing favouring cold and snow is that at no time does the jet stream appear to lift into a really mild flow and the cold high continues to lurk somewhere east of the Baltic. But I think it's more likely to push west more forcefully well into January 2013.


Forecasts for Britain

TODAY ... Variable cloud, showers, gusty southwest winds across south, last of southeast gales in northern Scotland fading away, rain or mountain snow in north also fading to showers. Winds generally 40-70 km/hr across the south will diminish later to 30-50 km/hr. Highs 7-10 C south, 5-7 north.

TONIGHT ... Cloudy, moderate southwest winds, a few more showers, lows generally 3-5 C.

OUTLOOK ... Similar pattern to Ireland from Sunday on, mostly rather mild with frequent showers in south but continued slight colder incursions from east or southeast affecting mainly Scotland and north-central England usually in the opening phases of each disturbance that comes along, and also a similar outlook for Christmas period, windy with mixed precip likely Scotland and northern England, rain or showers south.


Forecasts for North America

Cold and dry in northern New England, eastern Canada, but mild and dry in the northeast states otherwise, also lower Great Lakes, parts of Midwest and southeast, highs about 12-16 C. Light rain spreading out of central plains states into upper Midwest, mild with highs also 12-16 C. Some wet snow further north closer to Canadian border and back into higher parts of Colorado, Wyoming. Mixed showery precip from another weak frontal wave in the higher parts of the southwest although likely to stay dry in southern Arizona. A dry start on the west coast with heavy rain moving in later.

My local weather on Friday was sunny by mid-day with cloud at both ends of the day, highs near 7 C.

Important: Please note legal disclaimer which can be seen at bottom of post 2565 dated 24 July 2012.


Monday, 17 December, 2012

Forecasts for Ireland

TODAY ... Cloudy with some brighter intervals mainly across the south, light rain or showers, risk of hail and the odd rumble of thunder, also some sleet or melting wet snow possible on hills in northwest, feeling a bit colder in west to northwest winds 30-50 km/hr, and highs around 7-8 C.

TONIGHT ... The last of any mixed or sleety showers ending across the north, clearing more rapidly in the south, leading to some frost and icy road conditions in some inland regions after midnight towards dawn. Lows could reach -2 C in some places but on average will be near zero to +3 C.

TUESDAY ... Frosty and somewhat icy start, dry and partly cloudy daytime, some sunshine mainly in eastern counties, highs 6-9 C. Rain moving into west by late afternoon as winds pick up rapidly there from the southeast. Some heavy rainfalls likely overnight into Wednesday morning (15-25 mm) in gusty southerly winds.

WEDNESDAY ... Windy (SE to SSW 40-70 km/hr), periods of rain followed by showers -- this could start as sleet in north in the early morning hours, turning milder in stages, lows 0-3 C north but 4-8 C south, and highs reaching 7-11 C south and central counties, 6-8 C north.

THURSDAY ... Showers, windy (SW 40-60 km/hr), lows 2-4 C and highs 6-8 C.

FRIDAY ... Variable cloud, isolated showers, lows 2-4 C and highs 7-10 C. Some models hint that it could turn colder in Ulster as east winds seep back into the picture briefly but Scotland stands a better chance of seeing any snow from this brief interruption in the relatively mild spell.

SATURDAY ... Cloudy, periods of rain, mild (possibly very mild) lows near 6 C and highs near 11 C. Moderate to strong south to southwest winds.

SUNDAY ... Rain at times, mild, becoming windy especially in west and north with SW gales possible. Lows near 5 C and highs near 10 C.

MONDAY (Christmas Eve) ... Some indications of strong winds developing, continued rather mildr, winds SW 50-80 km/hr (possibly stronger) veering westerly. Highs about 9-11 C south and 7-8 C north. Winds may gust to about 100 km/hr in the north and 80 km/hr in the south.

TUESDAY (Christmas Day) ... As speculated, the models have flattened out the upper level steering winds so Christmas Day is back to what the research model was saying many days ago, mild and windy with the risk of some rain, probably more towards the north, and highs 8-11 C, winds WSW 50-80 km/hr.

OUTLOOK ... Windy or even stormy from 26th to 28th, a general cooling trend as winds turn more to W-NW but models indicate yet another reload of the mild southwesterlies in the last two days of the month. I think it could turn a lot colder just after New Years and the zonal pattern could either break down for a while or go into a higher amplitude phase (larger swings in temperature).


Forecasts for Britain

TODAY ... Cloudy, showers or periods of rain, turning slightly colder again, highs near 7 or 8 C except near 10 C in southern England. Winds veering westerly 40-70 km/hr.

TONIGHT ... Showers more confined to northern England and north Wales and becoming wintry over hills, some clearing elsewhere, cold. Lows 1-3 C for most, some isolated frost developing.

TUESDAY ... Sunny intervals, highs 5-8 C.

OUTLOOK ... Similar pattern to Ireland from Wednesday on, mostly rather mild with frequent showers in south but continued slight colder incursions from east or southeast affecting mainly Scotland and north-central England usually in the opening phases of each disturbance that comes along, with the new development that a brief return to colder east winds could push into Scotland and some parts of northern England around Thursday night and Friday, so that sleet or snow could briefly replace rain there, then also a similar outlook for the 22nd onward through the Christmas period, windy with rain but some higher elevation mixed precip likely Scotland and northern England, rain or showers south and becoming very mild at times. There could be some severe wind gusts in Scotland around Christmas Eve if the current models prove accurate.


Forecasts for North America

Rain turning to sleet in some inland parts of the northeast U.S. but further rain along the east coast, temperatures slowly falling from near 10 C to closer to 5 C, sleet turning to snow in parts of Midwest and lower Great Lakes. Cold and dry in many parts of the northern plains and Canadian prairies, but a storm hitting the west coast in the early morning hours will rapidly spread snow inland (rain on the coast) reaching Alberta and Montana by afternoon and evening. Amounts across the Pacific northwest and southern B.C. could average 20-40 cms but on the coast it will become more of a windstorm as the low tracks across northern WA state into southeastern B.C. and southern Alberta.

My local weather on Sunday (in advance of this storm) was cloudy with rain in the afternoon, turning more to sleet this evening but no accumulation of snow here (above 300m it turns to heavy snow). Winds are backing from SE to E at about 50 km/hr, the stronger gusts are likely to miss my location to the south but expecting strong W-NW winds later tonight and on Monday.

Important: Please note legal disclaimer which can be seen at bottom of post 2565 dated 24 July 2012.


Wednesday, 19 December, 2012

Forecasts for Ireland

TODAY ... Windy (SE to SSW 40-70 km/hr), periods of rain already mostly confined to northeast will be followed by partial clearing with isolated showers, turning milder with highs reaching 9-12 C south and central counties, 6-8 C north. Further rainfalls (from 0800h) about 5-10 mm in northeast and trace to 2 mm elsewhere.

TONIGHT ... Cloudy, periods of rain heavy at times in eastern counties (moving in from south, largely missing western counties although some light rain at times there) ... rainfalls 10-20 mm east, 3-7 mm west ... lows 5-7 C.

THURSDAY ... Further showers with some longer periods of light rain, as the heavier rain moves away from east during the morning ... breezy to windy (SW 40-60 km/hr) in western counties, highs 7-10 C. Foggy at times in east.

FRIDAY ... Variable cloud, showers, lows 2-4 C and highs 7-10 C. Rainfalls about 5-10 mm. The models seem to have lost interest in any return of east winds to any part of Ireland or Britain, and so far every deviation from straight zonal southwesterly "service" seems to be a wrong move no matter which model is concerned, so ...

SATURDAY ... Cloudy, periods of rain, mild (possibly very mild) lows near 6 C and highs near 11 C. Moderate to strong south to southwest winds developing. Rainfalls about 10 mm.

SUNDAY ... Rain at times, mild, becoming windy especially in west and north with SW gales possible. Lows near 5 C and highs near 10 C.

MONDAY (Christmas Eve) ... Breezy to windy, potential for winds SW 50-80 km/hr (possibly stronger) veering westerly. Highs about 9-11 C south and 7-8 C north. Winds could gust to about 100 km/hr in the north by evening or into Christmas morning. The chance of a white Christmas developing away from higher ground in the north seems slight at this point.

TUESDAY (Christmas Day) ... The most likely outlook is mild and windy with the risk of some rain, probably more towards the north, and highs 8-11 C, winds WSW 50-80 km/hr. However, there is some chance of a colder day if winds turn more to the northwest.

OUTLOOK ... This continues to be the situation: windy or even stormy from 26th to 28th, a general cooling trend as winds turn more to W-NW but models indicate yet another reload of the mild southwesterlies in the last two days of the month. It could turn a lot colder just after New Years and the zonal pattern could either break down for a while or go into a higher amplitude phase (larger swings in temperature). The models are not picking this up yet, but it is almost two weeks away.


Forecasts for Britain

TODAY ... Rain and moderate to strong SE winds veering more to SW later in the day, rainfalls about 15-30 mm, highs 8-11 C for most, 5-8 C northern Scotland and highest elevations elsewhere.

TONIGHT ... Showers or periods of rain, mild, southerly winds 30-50 km/hr, and lows 4-7 C.

OUTLOOK ... Similar pattern to Ireland from Thursday on, mostly rather mild with frequent showers in south but continued slight colder incursions from east or southeast affecting mainly Scotland and north-central England usually in the opening phases of each disturbance that comes along, with the new development that a brief return to colder east winds could push into Scotland and some parts of northern England around Thursday night and Friday, so that sleet or snow could briefly replace rain there, then also a similar outlook for the 22nd onward through the Christmas period, windy with rain but some higher elevation mixed precip likely Scotland and northern England, rain or showers south and becoming very mild at times. There could be some severe wind gusts in Scotland around Christmas Eve if the current models prove accurate.


Forecasts for North America

The northeast states will see sleet or wet snow in a developing northeast wind flow as the persistent low repositions offshore and pulls away, bringing sleet and snow to Nova Scotia and Newfoundland later today. A new storm is developing in Missouri, heading slowly towards Michigan (Friday's expected location) ... heavy rain will develop in the Ohio valley and lower Great Lakes with bands of sleet and freezing rain, snow further north. There are also outbreaks of snow in parts of the northern plains and southern prairies, with a new storm moving inland from the Pacific bringing snow to all but lowest elevations (rain near sea level). This will turn into a heavy snowfall event for most of the mountain ranges inland and eventually for Alberta and Montana.

My local weather on Tuesday featured the first significant snowfall (3-5 cm) that stayed on the ground all day in rather cold and foggy conditions, the high was only about 2 C, and we're now expecting another 5-10 cm snowfall later today (which has just started here at 1201h so time to post this!)

Important: Please note legal disclaimer which can be seen at bottom of post 2565 dated 24 July 2012.

Astronomy note: At 11:13h today, the winter solstice takes place -- this is the instant at which the Sun reaches its lowest declination or the point at which the earth's north pole points furthest away from the Sun (an angle of about 23.4 deg). The idea behind the "Mayan apocalypse" is or was that the Sun would also eclipse the galactic centre which is thought to be the location of a massive black hole. While this may well be true, the interaction is unlikely to generate any large effects and as I mentioned elsewhere, this eclipse is only marginally different from what has happened at the same time of year every year in the past few decades. But just in case, it's been really nice knowing you all.

Friday, 21 December, 2012

Forecasts for Ireland

ALERT for widespread dense fog and isolated frosty or icy sections on roads this morning. ALERT for heavy rainfalls tonight.

TODAY ... Foggy to start in many places, especially east-central inland, then becoming partly cloudy later, a mostly dry day other than fog or mist, with isolated showers developing west, highs 7-10 C mildest in southwest. Winds will become moderate southerly by afternoon.

TONIGHT ... Periods of rain, 10-20 mm arriving in west Munster in the evening and spreading to eastern counties by about midnight. Winds becoming rather blustery at SSE 40-70 km/hr. Temperatures about 5 C in the evening rising to near 10 C by morning.

SATURDAY ... Morning rainfalls of about 10-20 mm ending by late morning in Ulster and north Leinster, cloudy with drizzle or showers by afternoon, becoming milder with highs 11-13 C. Winds moderate SSW (30-50 km/hr).

SATURDAY NIGHT ... Another windy interval (SW 50-80 km/hr, gusts to near 100 km/hr in northwest coastal districts) with periods of rain, lows near 5 C.

SUNDAY ... Windy to start, with further rain or showers (10-20 mm total) and gusty southwest winds subsiding to westerly 40-70 km/hr, lows near 5 C and highs 8-10 C.

MONDAY (Christmas Eve) ... Breezy or windy with showers, turning somewhat colder in the afternoon or evening, winds SW to WNW 40-70 km/hr, lows near 4 C and highs near 8 C.

TUESDAY (Christmas Day) ... Cloudy with moderate west to northwest winds, passing showers that may be mixed or wintry over higher terrain especially in Connacht and west Ulster, highs about 7 C (but 3-5 C over higher parts of northwest). It appears a bit too mild for snow in most locations but there will probably be some reported in higher parts of Mayo, Donegal etc.

WEDNESDAY (26th) ... Windy with showers, somewhat milder again, highs near 9 C in strong west backing to southwest winds reaching 70-110 km/hr by evening.

THURSDAY-FRIDAY ... Windy and possibly stormy especially in Connacht and west Ulster, potential on current maps for wind gusts to 120 km/hr in north and 100 km/hr other regions. Highs about 7-9 C, frequent blustery showers or squalls of hail. As this storm will accompany the full moon, tidal ranges will be unusually high on west-facing coasts especially Galway Bay.

OUTLOOK ... Windy and turning colder in stages through the last few days of the year.


Forecasts for Britain

TODAY ... Showers becoming more isolated, some fog and drizzle, otherwise partly to mostly cloudy, outbreaks of light rain near south coast, highs 6-9 C.

TONIGHT ... Windy and turning milder in stages with temperatures 10-12 C in the southwest by morning. Rain will be heavy at times as it sweeps through central and northern regions. Winds SE veering SSW 50-80 km/hr.

SATURDAY ... Rain, heavy at times in south and Wales, very mild in southwest by afternoon and evening (12-14 C) but foggy and about 7-9 C further north and east. Winds SW 40-70 km/hr.

SUNDAY ... Breezy to windy and mild, showers or periods of rain, highs 8-10 although turning colder in Scotland by afternoon, winds generally WSW 50-80 km/hr but could gust to 100 km/hr around Irish Sea coasts and southwest Scotland.

OUTLOOK ... Windy and showery over the Christmas holiday period, mixed wintry showers possible over much of Scotland and northwest England at higher elevations and in Wales over higher summits. Highs generally 6-9 C. Stormy at times from 27th to 29th.


Forecasts for North America

Stormy across the lower Great Lakes with rain changing to heavy wet snow, heavy rain in northeast U.S. as far north as about central VT-NH, heavy snow or sleet likely in Montreal and over higher parts of northern New England, as storm intensifies with new centre north of Boston replacing the dying circulation over Ontario. This will all conspire to sweep colder air rapidly southeast across Florida with risk of severe storms in Miami and region, otherwise clearing and much cooler than recently in southeast states, highs only about 5 C in strong NW winds. Clear and cold further northwest into the heart of this arctic outbreak, but mild in Texas and southwest states, while snow develops over central to northern Rockies and rain changes to wet snow near the west coast in advance of another snowstorm due on Saturday there. Canadian prairies are in a gradually warming situation as waves develop over the Rockies, no major chinook warming but temperatures creeping up towards freezing from -15 C.

My local weather on Thursday was rather unpleasant, cold and wet with the 10 cm snow pack gradually melting in a steady rain at 5-6 C. There is still enough snow to make it look white away from roads and sidewalks, but a lot of ponded meltwater in parking lots and lower lying areas. This rain seems likely to turn back to sleet and then more accumulating snow by Saturday.

UPDATE _ Sunday 23 December 2012 _ 0215h
__________________________________________

In case you haven't been following the storm thread on boards or the IWO facebook alerts and you turn to this thread upon being rudely awakened (awoken?) by the wind, an ALERT is in place for wind gusts to 120 km/hr in eastern and central Ireland especially the Dublin, Meath and nearby counties region, as well as east Ulster. These winds have already hit western parts of Ireland with peak gusts reported to 71 knots at Mace Head (that's close to 140 km/hr). The south coast may not get quite as blustery (peak gusts may be 90-110 km/hr there) but current strong winds around Dublin could peak at about 120 km/hr in gusts from west about 0300h. The wind storm should let up rather soon in western counties and about 0600-0900h in the east, as the gradient pushes rapidly across Britain and into the North Sea by mid-day.

Winds will continue rather gusty all day but in the more tolerable 50-70 km/hr range once this blows through.

Important: Please note legal disclaimer which can be seen at bottom of post 2565 dated 24 July 2012.


Monday, 24 December, 2012

Forecasts for Ireland

TODAY ... Breezy with showers becoming frequent and merging to longer periods of rain, winds SW backing to S 30-50 km/hr, and highs 8-10 C. Rainfalls 10-20 mm possible but the rain should move east and let up by afternoon. Misty after the showers with perhaps a brief sunny interval during the afternoon.

TONIGHT (Christmas Eve to Christmas morning) ... A rather cold and unsettled pattern may produce sleety showers in places, with some local fog or frost, midnight temperature about 4-5 C, eventual lows by dawn about 2 to +3 C for most, -1 C possible in a few spots. The best chance of snow would be at highest elevations of west. The most likely place to encounter icy roads would be rural north Leinster and central Ulster. The most likely place to encounter Santa would be near the tree (or at my place, the fridge).

TUESDAY (Christmas Day) ... Cloudy with moderate west to northwest winds developing by afternoon after a rather calm morning, passing showers that may be mixed or wintry over higher terrain especially in Connacht and west Ulster, and which could become thundery with hail in some parts of the inland south and east with highs about 6-8 C (but 3-5 C over higher parts of northwest). It appears a bit too mild for snow in most locations but there will probably be some reported in higher parts of Mayo, Donegal etc. Some sunshine likely at times mid-day in Leinster and Munster. The day is really going to produce a wide variety of weather, as a weak low drifts through the south followed by a moderate northwest flow of showery and somewhat cold Atlantic origins, so a bit of everything may be encountered especially if you're driving any distances.

WEDNESDAY (26th) ... A cool and dry start with some icy roads possible in slight frosts, then windy with periods of rain that could begin with mixed wintry showers or sleet, becoming somewhat milder again, morning lows -1 to +3 C, highs near 9 C in strong west backing to southwest winds reaching 50-80 km/hr by evening. High tidal ranges on west coast.

THURSDAY ... Breezy to windy and mild, winds SW 50-80 km/hr, highs reaching 10-12 C late in the day, 5-15 mm rain heavier in west and south. High tidal ranges on west coast and near Cork.

FRIDAY ... Breezy to windy and very mild, highs 11-14 C, winds SSW 50-80 km/hr, showers or periods of rain. High tidal ranges continuing, full moon date.

SATURDAY ... Windy and not quite as mild, potential for very strong winds at times (at least 60-90 km/hr) from WSW, highs 8-10 C. High tidal ranges continuing.

SUNDAY ... Very windy and turning colder with mixed showers over higher parts of northwest, winds WNW 60-110 km/hr, highs near 7 C. High tidal ranges and possible storm surge conditions.

OUTLOOK ... Monday (31st) should be the last in a sequence of rather mild days with another blast of southwest winds but much like last year the charts currently show New Years Eve (midnight that is) turning much colder in strong west to northwest winds -- this may be wintry for a few hours but a more pronounced change to colder weather may require one or two more tries. Here's something very long-range -- I have research data suggesting very mild weather returning at times in late January then much colder in February. Maybe this year the cold will push west a bit more effectively than last winter when it made quite an impact on eastern England but failed to reach western parts of Britain or Ireland in much strength.


Forecasts for Britain

TODAY ... Cloudy, showers or periods of rain, mild, southerly winds at about 30-50 km/hr, highs near 10 C. Rainfalls 15-30 mm. This rain is spreading north and the showers in Ireland will spread into northwest England later to merge with this system.

TONIGHT ... Rain becoming showery, drizzle or fog and some areas clearing to become locally frosty, but lows in most cases 3-5 C.

TUESDAY (Christmas Day) ... Variable cloud, showers, highs 6-8 C. A bit of sunshine here and there.

OUTLOOK ... Windy and showery over the rest of the Christmas holiday period, mixed wintry showers possible over much of Scotland and northwest England at higher elevations and in Wales over higher summits on Boxing Day but turning milder by 27th. Highs generally 6-9 C rising to 10-13 C by Thursday 27th. Strong SW winds at times from 27th to 30th.


Forecasts for North America

A minor snowfall event (5-10 cm) is likely on Christmas Eve into Christmas Day in advance of a much stronger storm from the southwest on the night of 26th-27th -- that will turn snow to rain and bring in strong SE winds. Meanwhile, the Great Lakes region will be wintry throughout since the ultimate storm will also bring snow to them as it tracks through central NY state into New England. The plains states will be seeing outbreaks of light snow this morning clearing later before the arrival of heavier snow Christmas Day morning, continuing cold, but rather mild near the Gulf coast in heavy rain at times through the period. The southwest will have occasional showers, and western Canada will be cold with outbreaks of sleet near the coast and snow elsewhere, trending to clear and very cold in northern regions under strong arctic high pressure that will remain almost stationary near Victoria Island in the western arctic.

My local weather on Sunday was cloudy with light rain at times, just a bit too mild for snow at 5 C. Expecting wet snow to mix in today or tonight into Christmas Day, a sort of white Christmas ahead then.



Merry Christmas and Happy New Year to all

Important: Please note legal disclaimer which can be seen at bottom of post 2565 dated 24 July 2012.


Wednesday, 26 December, 2012

Forecasts for Ireland

ALERT for fast-moving band of moderate to heavy rain that could produce temporary poor visibility and ponding on roads mid-day, conditions should improve within 2-3 hours of any poor driving conditions, prepare for delays. The system should be oriented Donegal to Wicklow by mid-day and is moving east at about 80 km/hr.


TODAY ... ( St Stephen's Day) ... A dry start in the east and parts of the north but becoming windy with an interval of rain lasting 3-4 hours that could begin in north as mixed wintry showers or sleet, followed in the southwest by a dry interval mid-day, that also spreading rapidly east ... another interval of rain later in the day towards evening, highs 7-9 C except 10-12 C south coast, in strong south to southwest winds reaching 50-80 km/hr mid-day, veering more to west by afternoon and evening. High tidal ranges on south and west coasts. Rainfalls of 10-20 mm, expect some ponding on roads mid-day especially around Laois-Kildare.

TONIGHT ... Any further rain turning to drizzle or sleet then ending, some clearing, rather cold. Lows -1 to +3 C, icy sections on some roads inland north. Winds WSW 20-40 km/hr in exposed locations will keep west coastal temperatures 4-7 C.

THURSDAY ... Breezy to windy and slowly becoming milder, winds SW 50-80 km/hr, highs reaching 8-11 C late in the day after reaching about 6-8 C early afternoon, 5-15 mm rain heaviest in south, as once again a band of fast-moving moderate to heavy rain is likely but this time more concentrated across the south. High tidal ranges on west coast and near Cork. Heavy rain likely overnight into Friday in gusty south to southwest winds. 20-30 mm rain could fall in total.

FRIDAY ... Breezy to windy and very mild, highs 11-14 C, winds SSW 50-80 km/hr, showers or periods of rain. High tidal ranges continuing, full moon date.

SATURDAY ... Windy and not quite as mild, potential for very strong winds at times (at least 60-90 km/hr) from WSW, lows 3-5 C and highs 8-10 C. High tidal ranges continuing south and west coasts.

SUNDAY ... Very windy and turning colder with mixed showers over higher parts of northwest, winds WNW 60-110 km/hr, lows about 2-4 C and highs near 7 C. High tidal ranges and possible (minor to moderate) storm surge conditions west coast.

MONDAY (31st) should be the another rather mild day with southwest winds gusting to about 80 km/hr, periods of rain or showers, and highs near 10 C.

TUESDAY (1 Jan) may then turn a bit colder in strong westerly winds and the risk of blustery, mixed showers over higher parts of the north, then moderating. Highs near 6 C.

OUTLOOK ... At the moment most guidance for the period 2-5 January is showing a very mild southwest to west flow around high pressure setting up over the Azores to Portugal. If these maps verify, highs could be close to record highs at times, 12-14 C. This could change somewhat as we get closer to that time frame.


Forecasts for Britain

TODAY ... Variable cloud, dry start in some areas, afternoon showers or periods of rain, moving rapidly into Wales and the southwest mid-day and then rapidly east across England, gusty winds SW 50-70 km/hr veering westerly and highs 6-8 C (8-11 C south).

TONIGHT ... Foggy, rain ending, lows 2-5 C, moderate westerly winds.

THURSDAY-FRIDAY ... Periods of rain, highs about 7-9 C Thursday then turning even milder with gale force SW winds developing, heavy rain returning to southwest England possibly renewing flooding. Highs 11-14 C.

OUTLOOK ... Strong SW winds over the weekend, turning colder in stages with highs 7-9 C Saturday and 5-7 C Sunday. Similar further outlook to Ireland as posted above.

Forecasts for North America

The main story today is a slow-moving storm system bringing severe storms to parts of the southeast (into GA, SC later) and rain trending to ice and snow further inland north and west. The heaviest snows through tonight and tomorrow will probably be in upstate NY and northern New England as well as parts of southern Ontario and Quebec. Amounts of 20-30 cms are forecast for that region. The larger cities on the Atlantic seaboard will get sleet and rain mostly, with highs of about 5-8 C. Some wet snow could fall near the end of the storm event late tomorrow. Otherwise, the pattern further west is rather quiet as another weak system is forming over the Great Basin region with small amounts of snow over higher terrain. The west coast remains rather wet and chilly but above freezing with rain or sleet.

My local weather on Christmas Day was wet and the rain had some snowflakes mixed in at times but with no accumulation locally (heavy snow on some higher hills around) with highs about 4 C.

ADVANCE ALERT _ Thurs 27 Dec 8:15 p.m.
_________________________________________

ALERT for strong winds most regions, most intense west and northwest coasts, and possible minor to moderate storm surges on west coast and parts of south coast ... two peaks of wind speed can be expected, Friday afternoon/evening (SW 90-130 km/hr) and Saturday night into Sunday morning (WSW 90-140 km/hr). High tides Friday and Saturday nights could see overtopping of some seawall areas in Galway, Mayo etc. Would rate this about a borderline minor/moderate storm surge potential. Large waves and swells will be generated especially in the second phase and through Sunday as a very deep low will be moving slowly east about 60 deg N. If the gradient increases any further this alert may require an upgrade into the significant wind-damage category but for now would imagine the results will be largely similar to the previous event although felt over a larger area.

Watch for further updates.

UPDATE -- Friday, 28 Dec 2012 at 0500h

---

Full moon is timed for 10:21 today. This will interact with strong SSW veering WSW winds later today to create higher tides than might be anticipated from tide tables by 0.5 to 1.0 metres. It will be very mild until late today with temperatures in the 12-14 C range. Winds are expected to peak around 6-9 p.m. at SW 90-130 km/hr but may become almost this strong by mid-day on the west coast.

Although winds should slacken somewhat late tonight there will be another surge of very strong westerly winds late Saturday. These will also peak in the range of 90-130 km/hr from WSW, and by this time the sea state will be very disturbed from 3-4 days of continually building SW to W fetch around a slow-moving deep low further north -- this will result in 10-15 metre waves in marine areas not far from shore (7-10 m south of Ireland and 3-6 m Irish Sea). Some of these battering waves could combine with almost storm surge conditions of tides 0.8 to 1.2 metres above normal to create locally dangerous overtopping of shoreline sea walls in Galway Bay and other coastline areas facing west and to some extent on the south coast as well. Be advised to view from a safe distance and elevation although it will be so windy and cold by that point that viewing would also be very uncomfortable (not to mention darkness etc).

Winds should gradually ease again later Sunday to moderate westerly or WNW 40-70 km/hr. Highs on Saturday 7-9 C and on Sunday about 5-7 C.

Otherwise any updates would follow in general the earlier forecasts and I could mention that parts of the inland northeast U.S. have seen 15-35 cms of snow past two days with more to come on Saturday this time accumulating on the coast in NYC and BOS. I have been some distance inland from home base and here it has been cloudy, near -1 C with low cloud ceilings and the occasional skiff of snow or snizzle, the ground here is barely covered with 3-5 cms snow but that makes it look a lot more like Christmas.

Stay safe on your travels. -- MTC

UPDATE _ Sunday, 30 Dec 2012 _ 0945h
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ALERT for strong winds developing again late tonight peaking around 0200-0700h and probably strongest in the central counties from Galway to Meath, similar to the event before Christmas although I think it may not be quite that strong, winds about 80 km/hr gusting to 110 km/hr. Will re-assess this around 5-6 p.m. from later guidance -- the system is currently a long way out to the west near 30W and therefore the error potential is fairly wide compared to most systems.

The coldest air of this mobile pattern is currently overhead so it should start to feel milder late today and temperatures will be moving in the opposite direction to normal with a peak overnight then another falling off from that maximum during the day Monday. By New Years Eve (midnight) it will be feeling very cold in a blustery W-NW wind and wintry showers are possible with temperatures not much above 2 C. That colder spell won't last much longer than the average New Years -- well you know -- and it will turn a lot milder quickly enough 2nd-6th.

I am now back at home base where it's very foggy and about 3 C.

We should get back to regular forecast messages by Monday, but watch for an update on the strong wind potential before 6 p.m.