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

Wednesday, 16 December, 2020

Forecasts for Ireland


TRENDS for the week of 16 to 22 Dec 2020

-- Temperatures will average 1 to 2 deg above normal but it will be turning colder at the end.
-- Rainfalls will average near normal amounts (now that we've had most of the current system's rainfall).
-- Sunshine will average near normal amounts.


FORECASTS

TODAY will continue quite breezy and locally windy, as the storm blows itself out over west Ulster and later over the Hebrides. Winds generally southwest to west in most parts, 50 to 80 km/hr, some higher gusts currently around north Kildare and parts of Meath, Dublin should settle back into that range too. Less windy (currently) Mayo and west Galway will see a gradual increase to westerly 50 to 80 km/hr as a stronger gradient reaches those areas. Some areas of showery light rain continue, especially close to the decaying centre of the low (now near south coast of Donegal Bay), and in parts of west Munster. Later on, there will be a few brighter intervals especially near the southeast coast and into the north midlands. Highs near 11 C.

TONIGHT will be partly cloudy to overcast with a few showers, lows near 7 C.

THURSDAY will be overcast, breezy and mild with 10-20 mm rainfalls setting in after mid-day, highs near 11 C.

FRIDAY will see intervals of heavier rain in parts of the east during the first half of the day, then a general cooling trend as winds veer more southwesterly in the 50-80 km/hr range, lows near 9 C and highs 10 to 12 C.

SATURDAY will be breezy and rather cold with passing showers, winds southwest 50 to 80 km/hr, lows near 4 C and highs 7 to 9 C.

SUNDAY will be breezy and cool with fewer showers, some longer dry intervals, and bits of sunshine possibly, lows near 4 C and highs near 8 C.

MONDAY a final Atlantic storm in the series will arrive over the south with rain and moderate south to southwest winds, temperatures 8 to 10 C. Further north, an east wind will be fairly cold with a potential for sleety mixtures to develop, temperatures 3 to 7 C.

TUESDAY a secondary wave may form behind the Monday system and that one could track into the southeast pulling the colder air further south, so that many places could see a sleety mix of rain, wet snow and frozen mixed precipitation. The main question about that will be intensity, just light falls with a dusting, or more significant coatings possible? We will be keeping an eye on how this develops (for the 22nd).

WEDNESDAY colder with passing wintry showers, winds north to northwest 40 to 70 km/hr, lows near 1 C and highs near 5 C.

THURSDAY (24th) will be a cold, fairly bright day with isolated wintry showers, likely some small accumulations of snow on higher terrain, lows near -1 C and highs 4 to 6 C.

FRIDAY (Christmas Day) will also be cold and there are hints in some guidance of an interval of sleet or snow developing. One scenario is that a weak front moving in from the Atlantic could run into the embedded colder air and rain might turn to wet snow. Another scenario is that the flow turns more northeast then easterly, with snow possible.

OUTLOOK is for whatever colder air masses are then available to deepen their grip for a few days, with high pressure likely to prevail, so cold and dry is the likely outcome after Christmas. It looks about five degrees below normal rather than any brutally cold 2010-type scenario but still cold enough for snow in any east wind streamers.

My local weather has seen our predicted snowfall materialize and about 10-12 cms has fallen so far with about the same due later today. Temperatures are near -2 C. The northeastern states are bracing for a heavy snowstorm (mixing with sleet near the large cities), 15 to 30 cm amounts are possible, locally 30 to 50 cm in parts of West Virginia, Pennsylvania, central New York state and parts of New England. This will be lasting into Thursday.

Friday, 18 December, 2020

Forecasts for Ireland


TRENDS for the week of 18 to 24 Dec 2020

-- Temperatures will average near normal values with a generally downward trend through the interval, ending up around 3-4 deg below normal by the 24th.
-- Rainfall will be near normal or slightly below in some places.
-- Sunshine will be near average in this cloudiest part of the year.


FORECASTS

TODAY will be breezy and mild with heavy showers advancing from current location (west Ulster through midlands to inland southeast) to the east coast by later this morning. Some clearing will follow that band with further lines of showers, generally weaker, following on in a south to southwest wind flow reaching 40 to 60 km/hr at times. Highs around 12 C this morning with readings of 9 or 10 C common by afternoon.

TONIGHT will be breezy with passing showers or intervals of rain, winds southwest 40 to 60 km/hr, lows 4 to 6 C.

SATURDAY will have variable amounts of cloud and passing showers, some heavy with hail and thunder possible. Winds southwest 50 to 70 km/hr, highs near 8 C.

SUNDAY will be partly cloudy, dry for much of the day with isolated showers mainly in northern counties, then rain will arrive by late in the day with gusty south to southwest winds developing. Lows near 3 C and highs near 8 C, temperatures steady overnight.

MONDAY will see strong winds and briefly heavy rainfalls, followed by partial clearing and a drop in temperatures from readings 10 to 12 C early in the day, to around 7 C. Winds briefly as strong as 70 to 110 km/hr in some parts of the south, central and eastern counties.

TUESDAY will see some dry intervals but an area of sleety light rain may edge into the south with snow on hills by afternoon or evening, winds northeast 30 to 50 km/hr, and quite cold, temperatures steady 2 to 4 C.

WEDNESDAY will become more windy with little change in temperature (2 to 4 C) and mixed wintry showers especially if any bands form over nearby seas and the Atlantic Ocean, in northerly winds that may be quite strong over exposed coastal north and west in particular, 60 to 90 km/hr in places.

THURSDAY (24th) will continue quite cold and bright with passing wintry showers in a northerly flow of about 40 to 60 km/hr, some variations to northwest winds at times may bring in bands of wintry showers from the Atlantic, morning lows near -1 C and afternoon highs near 4 C, feeling colder in the wind.

FRIDAY (Christmas Day) is likely to remain cold and dry in most areas with just a slight chance of isolated wintry showers, also a good chance of a sharp frost in the morning, lows near -4 C for Christmas morning, followed by highs around 5 C later in the day.

The evolution of the pattern beyond Christmas Day is somewhat uncertain but much of the guidance has two elements worth noting, a brief milder turn in west-northwest winds that could become quite strong at times either on the 26th or 27th (or both), then a much colder turn to follow that as arctic air masses to the north of a frontal zone and then begins to move south in considerable force after about the 28th, with the New Years period indicated as being particularly cold and wintry. Snow is definitely a strong possibility if these changes materialize since winds will often be from either the north or northeast over those days (28th into early January 2021). I am being cautious about this change as there may be some chance of the milder northwesterly version digging in and holding back the full push of colder air that is becoming available, as low pressure develops over central Europe and high pressure builds across the far north to provide a source for much colder air to descend into western Europe on the northeast winds that would develop between these systems. The hitch may be persistent troughs lingering across the North Atlantic forcing the colder air to waste time going around the long way where it gets modified to an extent that makes it just chilly rather than bitterly cold.

My local weather on Thursday was mostly cloudy but no further snow has fallen, and it was around -2 C. The recent storm that hit the northeast U.S. left behind a zone of incredibly heavy snowfalls (40.0 inches at Binghamton NY, which is a little over one meter). The coastal cities had more like 20-30 cms with a thaw-freeze cycle turning much of that to icy slush. The storm responsible is now south of Nova Scotia heading east, and it's breaking up into smaller substorms that will spawn two or three disturbances affecting your weather from Sunday night on. If the third of this series were to deepen south of Ireland on Tuesday night that could lead to snow in parts of Ireland so it's going to be interesting to watch how things unfold. The first segment of the old storm will break off rapidly and bring in a brief shot of milder air and rain Sunday night. The second segment at this point looks a bit anemic and may just wander off into France on Monday night. Then comes that third part -- and around then big changes starting to take hold in the polar regions (in the upper atmosphere) will be poised to interact with this energy and that will dictate what happens around Christmas to New Years.

Sunday, 20 December, 2020

Forecasts for Ireland


TRENDS for the week of 20 to 26 Dec 2020

-- Temperatures will average 1 to 2 deg below normal.
-- Rainfall will average 50 per cent of normal values, possibly as low as 25 per cent in the north.
-- Sunshine will average 25 to 50 per cent above normal, although some days will be overcast.

FORECASTS

TODAY will bring a mixture of cloud and brighter intervals with passing showers, mostly confined to west and north. Highs 7 to 9 C.

TONIGHT will become wet in the south and central counties, with rain becoming steadier towards morning, and temperatures will only fall a little in the evening before becoming steady 5 to 7 C.

MONDAY the rain (10 to 15 mm totals expected) will gradually push east with a moderate southwest to west wind turning more northwesterly, with partial clearing. Highs 8 to 10 C.

TUESDAY will be rather cold, bright across Ulster, north Connacht and north Leinster, and mostly dry there also, highs 3 to 6 C. Further south it will be overcast and some light rain is possible, with sleet or wet snow on hills. Highs 4 to 7 C in those areas. Light easterly winds will develop.

WEDNESDAY there is some risk of snow or sleet in the morning across parts of Munster and south Leinster, likely to be melting on contact except on higher terrain. Further north, although mainly dry, some streamers could develop from the Irish Sea as well as the North Atlantic, bringing some parts of Leinster and north Connacht mixed wintry showers. Winds increasing to northeast 40 to 70 km/hr, lows 1 to 3 C and highs only 3 to 5 C.

THURSDAY 24th will be a cold, bright day with northeast winds turning more northerly, which may keep any Irish Sea wintry showers off or near the Wicklow coast. Dry in many other areas but there could be mixed wintry showers in west Ulster and north Connacht also, in northerly winds 40 to 60 km/hr. Lows near -1 C and highs near 5 C.

FRIDAY (Christmas Day) will have a frosty start and some icy road conditions are possible, inland east and south in particular will be quite cold with morning lows -2 to -5 C. Thick frost is possible for some areas although rising temperatures after midnight in the west may remove that frost before Christmas morning. Some hazy sunshine later through increasing high cloud, then becoming quite breezy (westerly 40 to 70 km/hr) by afternoon and evening, highest temperatures will range from 9 C in coastal south and west, to 5 C in east Ulster and north Leinster. Windy with occasional light rain or drizzle by the night of 25th-26th, temperatures may peak around 9 or 10 C at some early morning hours then a slow drop in temperatures will set in, winds quite strong at times may reach west-northwest 70 to 110 km/hr.

SATURDAY (26th) will remain windy, any milder turn (which some guidance shows briefly) will end with passage of a cold front, but some guidance already indicates the whole day will be quite cold as winds become northwest then north 50 to 80 km/hr. Morning lows 3 to 5 C then afternoon temperatures similar or falling slowly.

SUNDAY (27th) to MONDAY (29th) is looking quite cold with the risk of localized snowfalls, whether of streamer origins, or small low pressure areas rotating around a larger low in Belgium and northeast France. These lows could contain mixed wintry forms of precipitation near sea level and snow for hills, as temperatures will be struggling to get much above 4 C anywhere (and could be colder than that for parts of these days).

The further outlook is quite uncertain at this point, this colder air will try to hang around for several more days but the Atlantic resumes its active storm track too, so a clash is possible, guidance is mixed as to where the rain-snow boundary will set up, but it could be at least through some parts of Ireland, possibly dividing the country into somewhat milder and continued cold zones at times.

There is plenty of potential for occasional light snowfalls in all of this, but nothing that yet shows a high probability of being disruptive on a larger scale. Watching it all carefully of course.

My local weather has brought a nice steady light snow since mid-day when it was overcast and 3 deg C. Now it's closer to -2 C with 5 cm of new snow topping up the rather frozen covering we had as of Saturday morning. Another 10-15 cm could fall before skies clear (hoping they clear by evening as I have had very limited views of the Jupiter-Saturn conjunction).

Tuesday, 22 December, 2020

Forecasts for Ireland


TRENDS for the week of 22 to 28 Dec 2020

-- Temperatures will average about 2 or 3 deg below normal values. It will be turning much colder near the end of this interval after an earlier cooler period around starting today.
-- Rainfall will average 25 to 50 per cent of normal, some precipitation will fall in wintry mixtures.
-- Sunshine will average near normal values.


FORECASTS

TODAY will be a cold and almost calm day with cloud spreading a bit further north to obscure sunshine after mid-day in the north. A northeasterly breeze will pick up in southern counties this afternoon. Some light outbreaks of sleety rain or mixed wintry precipitation will develop late in the day across parts of the south. Highs only 2 to 5 C north, 5 to 7 C south.

TONIGHT there may be wintry mixtures of sleet, snow and cold rain across the south, with the greater likelihood of snow on higher terrain and well inland from the coast. The northern counties will remain partly cloudy to clear and that will allow temperatures to fall back below freezing there, further south lows will be around zero C to +3 C near the south coast. By morning there could be slushy accumulations of snow in some parts of the inland south.

WEDNESDAY will see this mixture of sleet and light snow continuing in parts of Munster and south Leinster, mixing with sleety rain near the south coast, leaving a coating of 1-3 cm in some areas (more likely inland and above 100m asl). It will likely stay dry north of about Clare to north Wicklow, except for any wintry showers that may form over east Ulster and parts of Mayo due to weak bands of streamers. These may move further south later in the day and affect the Dublin region. Winds will increase from light northeasterly to moderate north-northeast 50-70 km/hr, adding chill to temperatures that will be steady in the range of 2 to 5 C. The wintry mix will end rather gradually across the south, by afternoon in most places, but not until evening in Wexford. Some significant snow accumulations are possible on hills in the inland south and southeast (up to 5-10 cms but rather wet and partly melting after falling).

THURSDAY (24th) will see partial clearing from early morning, with morning lows near -2 C. Sunny with cloudy intervals during the day, except where bands of wintry showers form near east coast and north Connacht, west Ulster; local snowfalls on hills may amount to 1-3 cm in places although many areas will remain dry. A sharp frost is likely after sunset on Christmas Eve, following daytime highs of 4 to 7 C.

FRIDAY (Christmas Day) will start out frosty in parts of Leinster and Munster, east Connacht and east Ulster, where lows could be -2 to -5 C. Any frost further west will likely be removed before morning by a slight increase in westerly winds and cloud cover. Hazy sunshine will follow the frosts in some eastern counties, more overcast further west, but generally dry with moderate westerly breezes setting in. Highs near 4 C east to 7 C west, 9 C coastal Munster.

SATURDAY (St Stephen's Day 26th) will become windy with temperatures peaking at a rather early hour (possibly during the night of 25th-26th) at around 7-9 C, then it will begin to turn colder in stages with winds northwesterly at about 70-100 km/hr and passing showers, becoming wintry on hills later in the day as temperatures fall to around 3 or 4 C. Some heavy rain turning to mixed wintry showers may develop in this strong northwest flow, the risk of wintry conditions will be minimal at first but significant by evening.

SUNDAY (27th) and MONDAY (28th) are looking windy and cold with scattered wintry showers, many of them snow but a few of sleet or hail too near coasts, in strong northerly winds 60 to 100 km/hr, which will add quite a chill factor to temperatures barely above freezing in the daytime (1-3 C). Nights will not be exceptionally cold because of this constant strong wind, but could drop to -1 or -2 C inland. At some point around Monday 28th a low may form in this strong northerly flow, reducing the wind speeds as the slacker gradient crosses northern counties, but increasing the risk of widespread sleet or snow.

The OUTLOOK calls for further wintry weather conditions towards New Years with a growing possibility of significant snowfalls, as low pressure areas begin to form in the broad northerly flow providing a focus for more organized bands of snow or sleet at times. Temperatures will be well below average around zero or +1 C in the daytimes and around -3 C at night. Some of the guidance suggests that the cold spell will dig in and persist for some time into January, and there are also some hints of battleground scenarios where Atlantic moisture over-runs the cold air across Ireland leading to more snowfall. Conditions could become quite harsh in isolated higher terrain with blizzard like conditions possibly affecting free ranging livestock. At the same time, I should underscore the fact that there is some uncertainty about details and it seems likely that conditions will be rather variable from place to place in this coming cold spell, not everyone is going to see the same amounts of snowfall for example. The latest guidance looks very wintry indeed at times in January, and there is no trend towards any fast return to milder Atlantic-dominated regimes, in fact what seems more likely is a second strong northerly setting in around 4th January.

My local weather brought 5-10 cm wet snowfalls during the day and it has turned quite foggy with temperatures falling slightly this evening to -1 C. A strong low has moved right along the border and was overhead a few hours ago, and has now reached western Montana. Fairly soon it will be out into the northern plains states leading to blizzard conditions there and in some parts of the Canadian prairies too. Much milder air is being pulled in from Texas and this will overspread most of the eastern half of the U.S. until late Christmas Eve when the low will be over the Great Lakes, and a secondary low forms on the cold front. There will be very windy weather with a sharp temperature drop for the Christmas morning weather across the eastern U.S., brief rain, thunderstorms, sleet and snow bands in succession as temperatures are forecast to drop from near 15 C to -10 C in a matter of just a few hours. Heavy lake effect snowfalls will hit some parts of the Midwest and New York state, south-central Ontario.

Thursday, 24 December, 2020

Forecasts for Ireland


TRENDS continue about the same, average temperatures will be 2-4 deg below normal values, rainfall will be about half of normal and some of the precipitation will take wintry forms, sunshine a little above normal with the colder weather.


FORECASTS

TODAY will be bright and cold, with a moderate northerly wind of 40 to 60 km/hr. Some bands of sea-effect showers will form, moving in from the North Atlantic into Connacht and the midlands. As they get further inland and encounter higher terrain, some will begin to drop local sleet or snow, but amounts will be small. Shower activity over the Irish Sea may remain largely offshore but occasionally may move into coastal Wicklow and Wexford. Any that can climb up the east slopes of the Wicklow hills would likely turn to snow, if they can get that far west. Highs today will be in the range of 4 to 7 C, colder values inland north.

TONIGHT will see a widespread frost although it may not last until Christmas morning in parts of the west as cloud increases there, but otherwise lows could fall to the range of -5 to -2 C.

CHRISTMAS DAY will begin rather calm and frosty in the east and some parts of the midlands, inland south. It will likely warm up a bit faster in the west and north, eventually reaching 8-9 C there while further east highs of 4-6 C are more likely, but temperatures will be slowly rising by the evening hours in all areas, as a band of light rain moves down from the northwest.

SATURDAY 26th (St Stephen's Day) will be a windy and briefly milder day with the highest temperatures of 9 to 11 degrees occurring either in the late overnight or morning hours, with a gradual drop back to colder values (5 to 8 C) by afternoon and evening. Some outbreaks of rain are likely (5-15 mm) with winds westerly 60 to 100 km/hr.

SUNDAY 27th will turn considerably colder with mostly cloudy skies, a few breaks in the overcast here and there, and scattered wintry showers that may begin to drop small accumulations of snow mostly on hills at first, as temperatures will be steady in the 1 to 4 C range most of the day. Quite windy, northwest to north 50 to 80 km/hr, adding a chill factor that will make those readings feel closer to about -4 C.

MONDAY 28th will bring the risk of sleet or wet snow especially over eastern counties. The strong winds will abate for a while, except near the western coasts which will remain in northerly winds of 40 to 70 km/hr most of the day, with passing wintry showers. Lows near -2 C and highs 2 to 5 C for most areas.

TUESDAY 29th and WEDNESDAY 30th will remain in a rather cold northerly flow turning somewhat more westerly later, temperatures generally near 4 C in the daytime hours and dropping to -2 C or so at night, and occasional outbreaks of wintry showers likely, with partly cloudy to overcast skies and moderate wind speeds.

NEW YEARS EVE (31st) may see more organized wintry outbreaks of sleet or snow as low pressure from the north drifts down across the country, and temperatures may fall a few degrees further to near 1 or 2 C daytime, which could mean small accumulations of snow in at least those areas inland and a bit higher than sea level. This situation is of course a week away and the guidance could change in either direction, at the moment I would say it's a rather marginal but potentially significant snow scenario.

The OUTLOOK beyond that into the first part of January 2021 sees very little change in the pattern, rather cold with ongoing risks of wintry mixtures including some accumulating snowfalls, and temperatures generally rather low although not into the "frigid" category.

For that you need to be somewhere between my place and the big winter storm hitting the Midwestern U.S., all regions between here and there are currently -15 to -30 C under clear skies (snow and blowing snow has moved through Minnesota and into Wisconsin and northern Ontario). Much milder conditions prevail east of a slow-moving front in the Ohio valley to the lower Mississippi; temperatures near 15 C and heavy rain are being reported and this will soon reach the east coast and major cities of the U.S. northeast. A sharp drop in temperatures is coming tonight about when Santa arrives there (how he gets to travel and we don't is another story for another day).

Saturday, 26 December, 2020

Forecasts for Ireland


TRENDS for the week of 26 Dec 2020 to 1 Jan 2021

-- Temperatures will average 2 to 4 deg below normal values.
-- Rainfall will average 50 to 75 per cent of normal with some taking wintry forms.
-- Sunshine will average near normal for late December.
-- It will often be quite windy especially near the Atlantic coasts.


FORECASTS

TODAY will be windy with occasional rain, becoming rather heavy at times by afternoon and evening. Winds southwest to west 60 to 100 km/hr, except higher gusts at times near Atlantic coasts. About 5-15 mm rainfalls are expected. Some squally showers are likely by late afternoon and evening. Temperatures will be highest around late morning or mid-day (11-12 C) and will start to fall gradually thereafter.

TONIGHT will continue windy with passing showers, becoming wintry on higher terrain in the north. Winds westerly to northwesterly 50 to 80 km/hr. Lows 2 to 5 C.

MONDAY will be windy and cold, with the strongest winds near Atlantic coasts where northwest gales 70 to 110 km/hr are likely. Somewhat slacker winds will develop over the east as low pressure drifts down from the north, for some parts of the day winds may fall below 40 km/hr as a result. Scattered wintry showers will be largely rain or hail near sea level, sleet or snow on higher terrain. Temperatures steady in the range of 2 to 5 C.

TUESDAY will also be quite windy and cold, with the stronger winds returning to all regions as low pressure drifts away to the southeast. Bands of wintry showers may begin to drop sleet or snow on lower elevations as temperatures fall slightly to the 1 to 4 C range. Winds northwest 40 to 70 km/hr with some higher gusts.

WEDNESDAY and THURSDAY will continue cold, but not as windy, with wintry showers more isolated, and some longer bright spells. The clearer skies will allow overnight lows to fall below freezing, lows near -2 C and highs 2 to 5 degrees both days. Winds northwest 30 to 50 km/hr.

By late THURSDAY (New Years Eve) into FRIDAY (New Years Day), occasional light snow and very cold, lows overnight near -4 C and highs 1 to 4 C.

This cold spell shows little sign of weakening, or becoming more intense either, so we're stuck with marginal conditions for snow that will probably only deliver very much lying snow to hills, but there will be times when sleet or snow fall at lower elevations with a tendency to melt on contact near sea level.

My local weather on Christmas Day was overcast with a bit of fog from a low cloud ceiling barely above our elevation here, and a bit of drizzly light snow towards evening, temperatures on the cold side at -7 C. The eastern U.S. have seen their predicted heavy rainfalls and strong winds, and are generally into the colder air masses now, with further sharp oscillations in temperature in the days ahead, looking like snowstorms might become a feature of the east coast weather after New Years.

My apologies for the dropped day, think it was more of a wrong day label followed by blurring together of a whole string of rather similar days. But here's an updated forecast anyway with some new details from latest guidance.

TONIGHT will remain windy as temperatures gradually fall to about 3 C by morning, feeling more like -2 or lower in strong west to northwest winds 60 to 100 km/hr, with some higher gusts near Atlantic coasts. Occasional squally showers this evening, slowly moderating to passing showers that become somewhat mixed or wintry at higher elevations of the north and west by morning.

SUNDAY will be windy and cold with passing showers, some of them wintry especially over higher terrain where snow may begin to accumulate in places (mainly above 300m asl). Winds northwest 50 to 80 km/hr with some higher gusts in Atlantic counties. Highs 4 to 7 C, feeling like 1 to 3 C in the strong winds.

SUNDAY NIGHT into MONDAY MORNING, an area of low pressure dropping south across the Irish Sea may bring more organized bands of wintry mixed precipitation, it will probably be divided more by elevation than by region with some chance of lying snow at about 150-200 m asl by morning. Winds will remain strong northwest to north in the western half of the country, but will fall off to lighter values in the east as the slack pressure gradients near the low come into play there.

Later MONDAY the winds will pick up again in all regions, northwest to north 50 to 80 km/hr, so the afternoon will be windy and cold with passing wintry showers, again mixed by elevation, highs 4 to 7 C. Temperatures over higher snow covered areas could be considerably lower (1-3 C).

TUESDAY will be breezy and cold with passing wintry showers, lows near -1 C and highs near 5 C.

WEDNESDAY will be similar although with perhaps longer sunny intervals and more isolated wintry showers, lows near -2 C and highs near 4 C.

The New Years Eve into New Years Day interval will bring only slight changes with temperatures remaining in the same range (lows near -2 or -3, highs 3 to 6 C), some wintry showers more likely to be all snow moving through that period, as the marginal indicators start to edge more towards definite snow-friendly numbers, but even so a few locations near sea level would still likely see some mixing. Moderate northwest to north winds through this period.

Guidance for the period following New Years Day continues to be mostly cold and dry with higher pressure building up just to the north or northwest of Ireland. This argues for less widespread wintry showers but as winds turn a bit more northeasterly the possibility of some Irish Sea streamers comes into play, a bit too far out and indefinite to get very excited about that yet. The GFS model runs out to sixteen days and has nothing but colder than average temperatures indicated to end of its run (now 11th of January), on the other hand only one or two genuinely frigid days in that stretch, so would expect temperatures to average around 4 C daytimes and -3 C overnight, some individual days a bit lower than that. There's still plenty of time for an even more robust wintry set-up to develop in this generally favourable scenario. Hints of that come when a slight easterly is shown trying to get its act together around the 5th-7th of January.

My local weather appears to be quite cold with a bit of fresh snow, haven't been outside yet, going after I post this at least as far as the coffee shop down the hill. Stay safe and healthy.

Monday, 28 December, 2020

Forecasts for Ireland


The trends remain similar to the past several days, colder than normal, precipitation mainly showery and not overly heavy, some sunshine in the mix.

FORECASTS

TODAY will continue quite windy, especially over the western coastal regions, with northwest to north winds of 60 to 90 km/hr adding a chill to temperatures in most places around 4 to 7 C (some outer headlands in the west will be a bit milder as this strong wind interacts with ocean surface temperatures around 9 or 10 C). Bands of sleety showers will continue in a few places, sometimes rather heavy locally, and tending to change to sleet or snow when passing higher terrain.

TONIGHT will bring some intervals of sleety rain or wet snow, continued quite windy, lows 2 to 4 C.

TUESDAY will be partly cloudy with isolated wintry showers, cold and while not quite as windy, rather cold in the breeze (northwest 40 to 70 km/hr). Highs 4 to 7 C.

WEDNESDAY brings a risk of snow or sleet, depending on the track of low pressure trying to bring back a bit of milder Atlantic air. Most guidance shows this low tracking southeast into Kerry and south Cork before sliding back into the Atlantic. Areas to the north of its track could see 3-5 cm snowfalls or mixed rain and snow near sea level, so the track is important, any counties to the south of the track will see a slight rise in temperatures to 5-7 C and a bit of light rain, but areas to the north will have temperatures close to 1 or 2 C and wintry mixtures. Winds will turn light easterly during this event before resuming the northerly trend.

THURSDAY (31st) will be a cold, partly cloudy day with isolated wintry showers, lows near -3 C and highs near 4 C.

FRIDAY (New Years Day) is likely to be very similar, with partly cloudy to overcast skies, occasional light snow showers, and lows near -4 C, highs 3 to 5 C.

The OUTLOOK seems to be trending more towards a cold regime continuing for quite some time, those hints of a breakdown have disappeared from the models that had them yesterday, and the main trend seems to be towards more of a cold easterly flow into the first ten days of January, which could be a bit more conducive for snowfalls especially in Leinster and east Ulster, but also could bring even colder temperatures that start to get far enough below freezing at night that some persistent frost could develop.

My local weather on Sunday was once again overcast with temperatures around -5 C. Like yourselves, we find ourselves in a rather repetitive weather pattern although it's a lot less windy here, and a bit colder which is not unusual given we are at a higher elevation than the highest peaks in Ireland. The weather in eastern North America is rather cold at present but will warm back up to the 10-15 C range before New Years eve, with only slight variations to follow as the storm track is setting up over the Great Lakes region for a while. It does start to look rather wintry in New England towards the second week in January.

Wednesday, 30 December, 2020

Forecasts for Ireland


TRENDS for the week of 30 Dec to 5 Jan 2020

-- Temperatures will average 3-4 deg below normal values.
-- Rainfall will be rather slight and most precipitation that does occur will be wintry mixtures (amounting to 10-20 per cent of normal seasonal rainfall amounts).
-- Sunshine will be 25 to 50 per cent above normal except closer to average in the west.


FORECASTS

TODAY could still produce scattered outbreaks of sleety mixed precipitation, but two systems trying to produce this are both rather weak. The southern wave is moving through west Munster with light rain fringed by sleety mixtures that might coat some highways in the general area of Limerick to Waterford (and south into north Cork), but it appears that amounts may be trace to 1 mm at best. The mild sector of this disturbance is also weak and poorly defined but it has reached Kerry and brought temperatures there up to 5-8 C, this level of warming will perhaps catch some parts of southwest Cork before being pulled away to the south by this afternoon. Elsewhere, temperatures will be steady around 1-2 C. The northern wave in Ulster is bringing wintry mixtures to Northern Ireland mostly, and adjacent north Leinster and northeast Connacht, Donegal. Again, the main problem for this wave is a lack of energy and moisture, temperatures are conducive for wintry mixtures (0-3 C). The sea effect snow showers that might follow this system into west Ulster and north Connacht could be the best snow producer of this rather marginal day. Winds will pick up by mid-day to northerly 30-50 km/hr and stronger by afternoon, with the snow showers reaching parts of Donegal, Leitrim, Sligo, Mayo and possibly Galway.

TONIGHT will see some clearing and a reduction in the snow shower activity, very cold with lows near -3 C.

THURSDAY (31st) will be a cold, generally bright day with scattered wintry showers, some accumulations of snows on northern hills, and highs 3-5 C. New Years Eve at midnight, weather prospects are clear to partly cloudy, isolated snow showers, very cold, significant wind chill, temperatures -2 to -4 C.

FRIDAY (New Years Day) will be partly cloudy with isolated snow showers, lows near -4 C and highs near 4 C.

The OUTLOOK calls for a continuation of the cold spell with more of an anticyclonic influence, perhaps dropping overnight lows into the -6 C range. Daytime temperatures will remain about 2-5 C. Isolated snow showers are likely but mainly in streamers coming in from the Irish Sea, affecting mostly central Leinster. At first, nothing too heavy is expected, but the charts show this cold spell undergoing periodic reinforcements and there could be even colder and more severe winter weather in mid-January if the guidance proves correct.

My local weather on Tuesday was overcast and colder with temperatures stalled out around -5 C. Not much wind made this cold tolerable enough (for me at least). The eastern half of the U.S. is expecting a mild and rainy New Years eve into New Years Day with temperatures in the 10-15 C range. Any snow cover left from recent storms will be melting away and ski-ing conditions will deteriorate in New England. The weather is more or less ideal for western ski-ing resorts where they can actually open and serve customers (lockdown conditions vary considerably from state to state and province to province, we are in a relatively mild regime here in British Columbia so far).

Friday, 1 January, 2021

Forecasts for Ireland


The trends remain the same, 3 to 5 deg below normal in temperatures, fairly dry for most places, localized wintry showers tending to become more prevalent in Leinster towards the end of the week, and probably a bit more sunshine than is normally the case at this time of year.

With it being New Years eve where I'm located, here's a bit of a blog format discussion, as the outlook is fairly similar to past few days ...

High pressure is starting to build up closer to Ireland and is also connecting to other highs in northern Scandinavia and Russia. This will mean that the winds will slowly turn more to the northeast, settling in that direction (east to northeast) by about the end of this coming weekend. The weather will remain largely dry with a few weak outbreaks of mixed wintry showers each day. Today's batch will probably stay mainly over northern counties. Tomorrow could see a bit more widespread activity in the morning, as a weak trough moves south. By Sunday, the only potential for localized wintry showers will be sea effect streamers from the Irish Sea. One or two heavier snow showers are possible near the Wicklow mountains and south Dublin.

By about Tuesday the east-northeast flow could become strong enough and cold enough to produce some significant snow, but then this pattern will break down for a couple of days with low pressure heading south from near Iceland, to produce a reinforcement of the cold spell, and that looks fairly potent for the second week of January. Temperatures throughout this period will stay in a similar range, daytime readings of 3 to 6 C will be typical, and overnight lows of -4 to -1 C. Places with a lot of exposure to the sea could run a degree or two higher.

As with the past few forecast discussions, the situation continues to hold some promise (or threat if you prefer) of significant snowfalls and more severe cold, but the trends are just inching towards that rather than showing anything as dramatic as the signals we got in advance of the 2010 cold spell or the late February snowstorm in 2018. I don't think anyone following the weather would be surprised if something more dramatic developed at some point in this extended cold spell, but still no really firm guarantees (at least from this source).

My local weather on New Years Eve has been overcast and quite cold with a few snowflakes in the air, no new accumulations today, and temperatures close to -10 C.

We'll return to the usual format tomorrow, if I survive that long into 2021.

Sunday, 3 January, 2021

Forecasts for Ireland


TRENDS for the week of 3 to 9 Jan 2021

-- Temperatures will average 3 to 5 deg below normal.
-- Precipitation will be slight in many areas, with mixed wintry showers, amounting to 10 to 25 per cent of normal precipitation amounts at this time of year.
-- Sunshine will be 25 to 50 per cent above normal.


FORECASTS

TODAY will be cold with a northeast breeze of 30 to 50 km/hr. The morning will be sunny in most areas, then some increase in cloud will follow, especially near the east coast, with bands of mixed wintry showers expected to form over the Irish Sea, moving about one third of the way across the country before dissipating. Upper parameters are somewhat marginal for snow today, but some could be in the mix, along with sleet, hail or cold rain in various showers, and there could be a local rumble of thunder near the coast. Best chance for snow is probably above 250m in the Wicklow hills and adjacent south Dublin. Highs 2 to 5 C but feeling more like -2 C.

TONIGHT will become clear again in many areas with lows falling to -5 C in the west, -2 C east.

MONDAY will bring another round of increasing cloud in northeast winds, outbreaks of wintry showers, and the snow chances increase somewhat with slightly colder air aloft, but it will still be a similar mixed bag of precipitation types over a fairly confined area of central Leinster. There is also some chance of mixed wintry showers near the south coast. Winds east-northeast 40 to 60 km/hr will add quite a chill to daytime highs of only 1 to 4 C.

TUESDAY will continue in a similar pattern, partly cloudy with isolated wintry showers, moderate northeast winds, and lows -5 to -2, highs 1 to 5 C.

WEDNESDAY will see winds turning more northerly for a while, which will change the distribution of the mixed wintry showers, the west and north being more favoured for them. Winds north to northwest 40 to 60 km/hr. Lows in the range of -4 to -1 C and highs 3 to 6 C.

The outlook beyond that is for several more days of quite cold and slightly unsettled weather in a moderate northerly flow, possibly getting even a bit colder by the weekend of 9th-10th, although guidance begins to diverge into two camps after that, one saying repeated reinforcements of cold from a north through northeast direction, the other implying that the blocking will slowly break down as high pressure sinks further south, allowing a weak push of milder Atlantic air masses, although still with some frosts at night as it would not be a complete return to "mild zonality." No hunches as to which set of maps to believe, but noting that this early breakdown concept has come and gone a couple of times already, so it may just be small signals getting over-amplified down the road.

My local weather on Saturday was milder and rather foggy with a slight thaw going on, as temperatures pushed up to near 4 C at our elevation, and 8 C in local valleys. This milder wedge will move on by later today and we may see a resumption of snowfall by tonight.

Tuesday, 5 January, 2021

Forecasts for Ireland


TRENDS for the week of 5 to 11 Jan 2021

-- Temperatures will average 2 to 4 deg below normal, with a gradual increase towards near normal values at the end of the interval.
-- Precipitation will be slight in most areas, 10 to 25 per cent of normal values in occasional wintry showers.
-- Sunshine will be near or slightly above normal values.


FORECASTS

TODAY will continue very cold with moderate northeast winds, although some parts of the inland west will have lighter winds for at least the morning hours. Bands of mixed wintry showers will continue to feed into central Leinster from the Irish Sea, snow is only likely briefly in mixtures, or on hills. Rain, sleet and hail will also be possible at times, however, coverage is not large and amounts will be generally small. Some sunny intervals will return further west. Highs 3 to 6 C.

TONIGHT will see some clearing in parts of the west and inland south, lows there could fall to -5 C. Rather cloudy with a few weakening wintry showers in the east, lows -1 or 0 C.

WEDNESDAY will see wind directions slowly turning back to north-northeast, which may allow areas of wintry showers to develop in Ulster and Connacht, but coastal Leinster may still see some as well (inland drift may be limited with these). Still quite cold with highs 3 to 6 C, mildest in the southeast and near the northwest coasts.

THURSDAY and FRIDAY will continue very cold as a new batch of arctic air arrives from a northerly direction. There won't be much change in the weather from this current spell as a result except that wind directions will vary from north-northeast to northwest in this spell, probably continuing the tendency for wintry showers to cover more areas of the north and west, but occasionally still to be found in the east. Some minor variations within this regime may lead to weak frontal bands of mixed wintry precipitation that could see wet snow or freezing drizzle turning to a cold rain at times. Amounts will not be large, but this could occur both days. Lows will continue in the range of -4 to +1 C and highs in the range of 4 to 7 C.

SATURDAY will see mostly cloudy conditions with a weak warm front approaching, but it may take most of the day to get temperatures up very much from their early readings near 2 C, eventually it could be as mild as 6 to 8 C.

SUNDAY and MONDAY at this point look milder again with highs closer to normal values, around 9 to 10 C, with some light rain at times.

The models are generally swinging back to seasonably mild weather patterns after that, although some have a cold day or two wedged into that milder regime. Not very confident of model scenarios past five or six days at this point and certainly seems quite plausible that a second and perhaps more severe cold spell could develop later in the month, but beyond the reach of the guidance at present.

My local weather on Monday turned a bit colder with a fresh 5 cm snowfall and temperatures stalled out around -2 C.

Thursday, 7 January, 2021

Forecasts for Ireland


TRENDS for the week of 7 to 13 Jan 2021

-- Temperatures will average 2 to 4 deg below normal, with a gradual increase starting around Sunday.
-- Rainfall or mixed wintry precipitation will amount to 25 per cent of normal values.
-- Sunshine will be near normal values.


FORECASTS

TODAY will start out with widespread icy and/or snowy conditions, except near the south and west coasts, any distance inland roads may be icy and quite slippery in places due to earlier or ongoing freezing rain, freezing drizzle or mixed sleety falls. In much of central, inland southeastern and inland northern counties, snow has fallen and will continue to accumulate perhaps another centimetre or two, before ending or changing back to sleet for a time. Then by mid-day into the afternoon, a cold northerly flow will arrive with bands of mixed wintry showers moving into western counties from the Atlantic, and possibly down the east coast also, in north to northwest winds 30 to 50 km/hr. Very cold with highs only about 2 to 4 C. Some snow-covered areas may hold near freezing until the snow is gone.

TONIGHT will see some clear intervals, isolated wintry showers, and very cold again with lows near -4 C.

FRIDAY will have variable amounts of cloud and a cold northerly wind, with scattered wintry showers, some accumulations of snow are possible near east coast and on hills. Highs 2 to 5 C.

SATURDAY will be partly cloudy with some locally persistent freezing fog, morning lows -6 to -2 C, afternoon highs slowly inching past freezing in most areas to the 2 to 5 C range, could reach 7 to 9 C in some outer (west, north) coastal areas.

SUNDAY will be similar although the milder air will sluggishly make inroads and bring temperatures up a few more degrees in many areas, lows -2 to +3 C and highs 5 to 9 C.

MONDAY to WEDNESDAY the milder air will continue to push rather weakly against the entrenched colder air which will only move slowly away from Ireland and then Britain, possibly returning briefly in some areas mid-week. Highs will edge up to more normal values 8 to 11 C. There won't be much if any rainfall in this regime, possibly a few light outbreaks amounting to 5-10 mm total.

The longer term outlook then calls for a return to colder weather on east to northeast winds some time around end of next week or the weekend of 16th-17th. Guidance probably becomes quite unreliable as to strength and duration of that cold spell since part of the justification for it involves near-term but future stratospheric changes.

My local weather brought another round of snow reaching about 10 cm by late morning when it began to taper off to drizzle; we escaped the worst of the mixed precipitation which came inland with the decaying Pacific storm and was cut off more by elevation than any other factor; rain fell during the day as close to us as Spokane WA. Temperatures here were around zero or +1 C, down there about 7 C.

Stay safe if you have to travel today, some driving conditions are likely to be quite poor especially on less travelled routes.

Saturday, 9 January, 2021

Forecasts for Ireland


TRENDS for the week of 9 to 15 Jan 2021

-- Temperatures will average 2 to 4 deg below normal, despite one or two days around mid-week pushing above normal slightly.
-- Rainfall will average 50 to 75 per cent of normal, most of it taking place around Wednesday.
-- Sunshine will average slightly above normal.


FORECASTS

TODAY will start out bitterly cold with widespread wintry sunshine but some local ice fog patches possible. With very light winds, the air mass will not allow any milder air to mix down in many areas, so temperatures will only gradually edge back towards freezing and highs near 2 C. Closer to the west coast however, there will be a more significant warming trend with highs reaching 7 C. Some scattered outbreaks of drizzle will occur in the northwest but it should remain dry although perhaps icy in most other regions.

TONIGHT there will continue to be some frosts although not as severe, with lows -5 to -2 C, staying closer to +1 C near west coast. Skies will be clear to partly cloudy, with some patchy overcast and drizzle in the north.

SUNDAY will become partly cloudy to overcast with some light rain in the west by evening. Highs near 4 C in the east to 8 C west.

MONDAY will be overcast with showers or intervals of light rain, temperatures steady 4 to 7 C (slightly higher near Atlantic coasts), and it may begin to turn a bit colder again in Ulster and north Leinster by evening.

TUESDAY a wedge of cold, dry air over Britain will perhaps influence east Ulster and north Leinster where highs may be capped at around 5 C, but further west, mild air will slowly push in from the west, raising temperatures to the range of 8 to 10 C, with occasional light rain developing overnight.

WEDNESDAY will become quite mild in all areas with highs 10 to 12 C, and about 10-15 mm rain is likely. This will push off to the southeast during the afternoon, and slightly cooler air will return by the evening.

THURSDAY will be partly cloudy to overcast with lows near 1 C and highs near 6 C.

FRIDAY will be overcast with lows near -1 C and highs near 7 C.

The outlook for next weekend is for another wedge of milder air to arrive on Saturday, with some rain likely, highs near 10 C, then a bit cooler by Sunday (around 7 C). The evolution beyond that is somewhat in doubt, quite a bit of the guidance has colder air building in from the north around the start of the week (18th Jan), other sources suggest mild regimes holding on for a while with cold massing just to the north. Either way there are prospects for a return to very cold temperatures at some point towards the end of January.

My local weather on Friday was mostly cloudy with a few breaks in the overcast, and highs near -1 C.

Monday, 11 January, 2021

Forecasts for Ireland


TRENDS for the week of 11 to 17 Jan 2021

-- Temperatures will average near normal to 1 deg above normal.
-- Rainfall will average near normal to 25% above normal.
-- Sunshine will average 50 to 75 per cent of normal.


FORECASTS

TODAY will be overcast with occasional rain, becoming heavier by afternoon before ending from west to east for a time this evening, highs 8 to 11 C. About 10-15 mm rain expected.

TONIGHT some clearing will spread into parts of Ulster where it may turn quite cold briefly, lows 2 to 4 C. Otherwise it will stay overcast in other regions with fog and occasional light to moderate rain, lows 6 to 8 C.

TUESDAY will see some further rainfalls of 10-15 mm with occasional heavy showers, and moderate southwest winds. The colder air in Ulster will be pushed back to the east by mid-day and all regions will then be around 9 to 12 degrees.

WEDNESDAY the rain will end by mid-day (about 20-30 mm additional expected) and it will begin to clear late in the day. Temperatures steady 10-12 C then falling slowly to around 7 C.

THURSDAY will be partly cloudy and a bit colder with lows near 4 C and highs near 8 C.

FRIDAY will be breezy and mild with occasional rain, southwest winds 50 to 80 km/hr, highs near 10 C.

The OUTLOOK for the weekend is for westerly winds and slowly falling temperatures in several stages, as winds become more northwesterly. Some showers are likely at times, with readings near 8 C on Saturday and 6 C by Sunday.

Next week looks colder again, with winds more northerly, highs only in the range of 3 to 6 C and possibly even colder, depending on which guidance prevails, as some of the charts by mid to late week (20th-23rd) show very cold air even a bit colder (in the daytime at least) than what was experienced last week, potentially some snow showers with that if not intervals of snow, much depends on wind directions and embedded low pressure in this arctic air, and daytime readings in the range of -2 to +2 C. This is certainly not "carved in stone" yet, but has been a fairly frequent theme of almost all guidance from time to time in the past few days. Then the least certain aspect of all is how long this second cold spell might last once underway, there were early suggestions it would be about a 3-4 day event but now it's looking possibly more like a week to two weeks.

My local weather continues in the "featureless" mode that we've come to expect, overcast skies, no precipitation, temperatures just around the freezing point. But we are expecting a heavy dump of snow here late tonight into Tuesday, possibly lasting through Wednesday and bringing at least 20 cms. The weather across eastern regions of North America is rather cold but dry, and it's mild and dry well to the south of my location across the southwestern and south central U.S. ... for this time of year, the pattern across North America is rather inactive with few instances of winter storm conditions. Meanwhile that snowstorm in Spain the other day broke into two pieces over the Mediterranean, largely jumped past Italy in the process, and the more active half moved into the Balkans where some areas got heavy snow, the remnants are now over the Black Sea.

Wednesday, 13 January, 2021

Forecasts for Ireland


TRENDS for the week of 13 to 19 Jan will all be fairly close to normal values.


FORECASTS

TODAY will see the last of the heavy rainfall in parts of north-central Ireland moving further east and into the Irish Sea. Some outbreaks of lighter rain may continue but there will be longer dry intervals, partly cloudy to overcast skies, some mist and fog especially on northern hills, and it will be quite mild, with highs 11 to 13 C.

TONIGHT an area of light rain will move in from the Atlantic and winds will gradually turn more westerly and then northwesterly, with slowly falling temperatures. About 5-10 mm rainfalls are expected with this, heaviest across central counties and later into the inland southeast. Lows about 6 C by morning.

THURSDAY the last of this secondary rainfall area will move off the southeast coast and the rest of the day should be essentially dry and a little cooler with highs 6 to 8 C in moderate northwest winds 30-50 km/hr.

FRIDAY morning will be clear and frosty especially in the eastern half of the country, lows -2 to +3 C, then clouds will slowly increase ahead of an area of rain expected to hit the west coast around late afternoon. Highs will reach about 5-7 C in most areas, 7-10 C on the west coast. The evening and overnight hours will become blustery with heavy rain at times, and winds southwest 50 to 80 km/hr. Temperatures will tend to rise in most areas rather than the usual fall expected at night, and may reach 10 C at around 0300h Saturday.

SATURDAY the cold front of this system will race through in the morning, clearing skies and turning winds westerly at about 50 to 80 km/hr, with possibly higher gusts especially near west-facing coasts. Isolated showers may develop in this windy regime and temperatures will be slowly falling through the day from morning values near 8 C to late afternoon readings closer to 4 C.

SUNDAY will be partly cloudy and breezy, rather cold, with passing wintry showers on higher ground. Lows near 2 C and highs near 7 C.

MONDAY one last mild sector in this series will race through probably during the first half of the day, with outbreaks of heavy showery rain and winds southwest to west 80 to 110 km/hr, then it will turn considerably colder and there may be some outbreaks of sleet or snow in strong northwest winds. Temperatures near 7 C at first, later close to freezing.

The OUTLOOK has become quite uncertain but most guidance does agree on a cold, rather dry pattern setting in for a few days. Almost anything could happen later next week as guidance splits into many different camps, some show wintry storms developing with this cold hanging on or trying to deepen slightly, others show a fast return to mild weather and rain. We'll have to wait a few days to get any real clarity on which scenario is going to win out, but expect mid-week temperatures to be on the cold side around 5 C daytime and -2 C at night.

My local weather saw the snowfall continue to mid-day, then change over to light sleety rain at times, and it has become quite foggy as temperatures are trying to push up above 2 C. The total snowfall over two days amounted to around 20 cms. When we have nicer weather later this week I'll try to get some photos of the rather impressive snow banks all around the town, haven't been up into the higher elevations yet this winter but I'm guessing from the talk I hear that there's over a metre of snow in the bush a few hundred metres higher up than the town which has about 60 cms level snow now (where not plowed, they tend to plow the streets, sidewalks and spaces in between all in one operation and so you tend to lose track of how much snow there is until you find some undisturbed ground, but there's a good two feet in the old system).

Thursday, 14 January, 2021

Forecasts for Ireland


TRENDS for the week of 14 to 20 Jan 2021

-- Temperatures will average 1 to 2 deg below normal values.
-- Rainfall will average 50% to 75% of normal values.
-- Sunshine will average near or slightly above normal.


FORECASTS

TODAY will be rather cloudy with some brighter intervals developing. Most if not all areas will have dry conditions or at worst, brief intervals of drizzle or light rain in parts of the southeast. Winds will gradually become northwesterly at about 40-60 km/hr. It will be cooler than yesterday but not particularly cold at 7 to 9 C.

TONIGHT will be chilly as skies clear to allow for frost and some dense fog patches, especially in the inland lowland areas of the southeast and central regions. Lows -3 to +2 C.

FRIDAY will start out with some sunshine through increasing high cloud. You may spot a solar halo around mid-day as clouds thicken, then by evening it will be raining on the west coast but remaining dry to about midnight further east. Rather cold most of the day and getting milder in the evening to midnight/0300h period, temperatures rising slowly to around 7 C in the afternoon and 10-12 C overnight. Not very windy but somewhat stronger winds developing in the evening and overnight (southwest 50-70 km/hr).

SATURDAY the cold front of this system will sweep through around 0300-0600h and partial clearing will follow as the rain ends quickly (10-15 mm expected by Saturday morning). The partly cloudy, breezy and cooler conditions will continue in the afternoon with temperatures slowly falling from morning highs of 10-12 C to afternoon readings near 7 C.

SUNDAY will be partly cloudy with some good sunny spells in places, and moderate temperatures, a slight frost to start in some inland areas, lows -2 to +3 C then afternoon highs near 7 C.

MONDAY will be overcast with rain becoming heavy at times by end of the day, strong south to southwest winds developing, lows near 4 C and highs near 10 C.

TUESDAY ... the outlook has changed somewhat as this Monday low is now moving east somewhat slower than earlier expected, and won't be past the Irish Sea until about mid-day Tuesday. Therefore Tuesday will start out still rather mild and wet, with cooler air arriving in two waves, one around mid-day dropping temperatures to about 6 C then a second cold front in the evening pushing readings down to freezing or -1 C. Showers and strong westerly winds of 70-100 km/hr will evolve into wintry showers and snow on hills with northwest winds 80-110 km/hr with strong wind chill values by Tuesday night.

The OUTLOOK remains a bit uncertain although various models seem to be converging on a shared solution -- cold air will build in for several days, it may not be quite the coldest possible air mass but it will feel very cold in brisk winds, daytime temperatures 2-4 C and overnight lows -4 to -2 C, passing wintry showers in northwest winds sometimes backing to southwest as troughs rotate around the now-stalled low (from Mon-Tues) parked near the coast of Denmark with a trough to another weaker low near the Orkneys north of Scotland. The big question is, how long will this cold air remain in place before the Atlantic, showing signs of re-energizing around Friday 22nd, pushes back with mild air and rain? Some models say the cold air will hold it back for several more days and yield around the 27th for a time, but with the cold air not pushed very far north and looking like it could make another surge to the south by early February. Other guidance suggests the milder flow will win out around the weekend of the 23rd-24th but it could come in with bands of snow, sleet and rain in succession as the cold air will be reluctant to leave such wonderful surroundings.

My local weather involved a damaging windstorm at dawn; a large tree crashed down across the neighbour's front porch (luckily that house is unoccupied and for sale), the tree being totally uprooted by strong gusts. A deep low pressure area moved past us to the north and raced through Alberta later on (Wed afternoon local time) and is now in North Dakota. This is the low that will show up on Atlantic weather charts over eastern Canada by Sunday, a low heading into the Atlantic by Saturday is already moving through the southeast U.S. bringing them some sleet and light rain. This second low will probably stay west of Greenland when it recurves to the north on Sunday but new lows will form from its extensive warm sector by then. It's those new lows which are complicating the outlook (at this point the genesis for them would be very subtle waves along a cold front in the central U.S.). I can understand why computer models struggle with all these developments when they have to start with two systems that are so far apart now (this low and the Scandinavian high pressure promoting cold air) but will interact somewhere in between a week from now. Anyway, getting back to my local weather, the rest of the day stayed rather windy and the early morning mild temperatures near 5 C quickly fell back below freezing, resulting in all the slush created freezing up, and it was dangerously icy around our town by evening, and around -7 C. The low created a blizzard across some parts of the prairies (well to the north of the international border) and strong but mild westerly winds closer to the border -- it wasn't a true chinook as the air mass was only downsloping briefly and the stronger winds were well out into the flat country rather than near the mountain passes. I'm estimating gusts to 120 km/hr at my location based on how trees were swaying and howling noises -- we tend to get very strong winds here when a westerly wind hits as there's a gap in the local mountain range that funnels them, a strong northwest wind regionally doesn't do the same thing here.

Saturday, 16 January, 2021

Forecasts for Ireland


TRENDS for the week of 16 to 22 Jan 2021

-- Temperatures will average 1 to 3 deg below normal. It will be near or slightly above normal to mid-day Tuesday, then considerably colder for most of the second half of this interval, reaching 4-5 deg below normal at times then.
-- Rainfall will average near normal values, however, almost all of it (now that last night's event is done) will occur on Monday night and Tuesday morning. Wintry showers will follow but these will not give much moisture.
-- Sunshine will average 25 to 50 per cent above normal as all days except Tuesday are likely to bring some sunny intervals. January so far has averaged about 50 per cent above normal over a grid of reporting locations.


FORECASTS

TODAY will be cloudy with sunny breaks, these more frequent in the east and south. Occasional showers will be fairly frequent in the northwest and less frequent elsewhere, amounts generally around 1 mm but locally 3-5 mm in the northwest. Moderate westerly winds 40-60 km/hr (higher gusts near Atlantic coasts) and highs 6 to 9 C.

TONIGHT will be partly cloudy to clear and some frost will develop, lows -3 to +2 C.

SUNDAY will be sunny with increasing cloudiness, highs near 7 C.

MONDAY will see some brighter intervals at first in the east and southeast, rather cloudy in other regions. One weak front will be edging into Ulster from the Atlantic during the day, while a stronger warm front moves into the southwest by late in the day, bringing rain and moderate southeast winds there. Morning lows -2 to +3 C and afternoon to evening highs 9 to 11 C.

TUESDAY will see intervals of moderate to heavy rainfall, moderate south to southwest winds, and temperatures steady near 10 C. Much colder air will arrive in the northwest by late afternoon and will push into all other regions between then and midnight. Winds rather moderate with this system, as it has a lot of small trough features and the strongest winds will blast around the western periphery offshore, Belmullet may catch those at times on Tuesday night. Temperatures will fall to around 2 C in many areas by late evening and to -3 C by Wednesday morning, as sleety showers turn to snow especially over hills.

WEDNESDAY will be windy and cold; the offshore strong west to northwest winds will move onto land in the morning and spread through all regions by mid-day, reaching 70 to 110 km/hr. Bands of wintry showers will form over the Atlantic and move inland, turning increasingly to snow as they get further inland and especially so when crossing higher ground. Some hail showers may also be in the mix, but the east and south will have some sunny intervals. Morning lows near -2 C and afternoon highs 2 to 4 C but feeling more like -5 to -8 C in strong winds.

THURSDAY will be similar except that the wind speeds will be down into a more moderate range of 50 to 80 km/hr, temperatures in a similar range (-2 to 3 C) and scattered bands of wintry showers with some snow accumulations possible on hills.

FRIDAY will be less windy but will remain cold, with sunny intervals and isolated wintry showers. Lows near -5 C and highs 1 to 4 C.

SATURDAY remains a day of some mystery as model guidance ranges from a brief return to milder conditions with rain, to mixed bands of rain, sleet and snow from south to north, and also some scenarios of a wider snowfall event with strong east winds. Stay tuned on this one, it could go either way (I can predict who already said it will rain).
Temperatures will be determined by which outcome prevails, the all-rain scenario would see a quick rebound to the 8 to 10 C range, the mixed bands would run from that value in the south, to 1-2 C north, and the mostly snow and south coast sleet scenario would probably involve temperatures near or slightly above zero.

By SUNDAY that disturbance, on whatever track it chooses to take, should be over Britain or northern France and colder weather would set in again briefly, with temperatures near 2 C and north to northeast winds. There could be some localized wintry showers with that.

The OUTLOOK for the following week is somewhat uncertain but would most likely see a succession of lows crossing Ireland with mixed bands of precipitation ranging from rain in the south to snow in Ulster and north Leinster. This could shift a bit in either direction, but a lot of the guidance ends mid-week so there is only one model to consult for the second half of the week; that one was trending milder at that point. But the others looked like they might not necessarily follow that lead.

My local weather on Friday was very pleasant for this time of year, sunny with light winds, and a bit of warmth at mid-day (highs 4 to 7 C across the region), but quite cold as soon as the sun set, with clear skies. This allowed me to check for any signs of fading Jupiter, I knew that Saturn must be lost in the solar glow by now as it will be behind the Sun by the first of February, Jupiter is heading there too by mid-February. The local hills blocked out my view of Jupiter even as early as sunset, but there was a pretty crescent new moon with the earthshine on the dark portion quite prominent (meaning I could see the entire globe of the moon despite only the bottom 10% being in sunlight). I noticed also that Mars is considerably dimmer than at its close opposition in the autumn, it now looks no brighter than Aldebaran, the red star in Taurus (which you can see to the upper right of Orion on these winter nights). Have a look this evening and see how the Moon is looking with a bit more illumination by then.

Monday, 18 January, 2021

Forecasts for Ireland


TRENDS for the week of 18 to 24 Jan 2021

-- Temperatures will average 1.5 deg below normal, a blend of 3-4 deg above normal to early Wednesday and 4-5 deg below normal thereafter.
-- Rainfalls will average near normal to 25% above normal, and most of that will fall on Tuesday and Wednesday (some will be sleet or snow).
-- Sunshine will be near normal by end of the interval, despite mostly cloudy skies for the first three days.


FORECASTS


TODAY will be overcast with outbreaks of light rain starting in the southwest by afternoon, spreading somewhat further north and east. Another area of light rain may brush parts of the northwest coastal areas. Highs 7 to 9 C.

TONIGHT will be mild with fog and occasional rain, 5 to 15 mm by morning. Lows 7 to 9 C except 3 to 5 C in parts of Ulster. Winds in most areas will become southeast to south 40 to 60 km/hr, backing to northeast in parts of Ulster.

TUESDAY will see rainfalls of 10-20 mm additional, with winds remaining moderate southeast to south 50 to 70 km/hr for most, easterly 40 to 60 km/hr in Ulster. Foggy at times especially over higher terrain, highs 10 to 12 C. Bands of heavier rain likely in central counties towards south Ulster, totals may reach 50 mm there by Tuesday night with flood risks in poorly drained areas.


WEDNESDAY the rain will continue but will begin to turn to sleet and wet snow, from early morning in parts of the north, mid-day in Leinster, with snow starting to accumulate just before ending late in the day. Winds becoming northerly 40 to 60 km/hr, temperatures near 8 C in the morning in the southeast, otherwise 2 to 4 C most other areas, and those readings will reach the southeast by afternoon. Around +1C by evening with slushy accumulations on lower ground in Leinster, 5-15 cm snowfalls on hills.

THURSDAY will become windy and colder, with bands of wintry showers, snow the main component inland on hills, sleet at somewhat lower elevations and rain/hail/sleet mixtures near sea level. Some sunny intervals between the bands of showers, winds northwest 80 to 110 km/hr. Morning lows near -1 C and highs 1 to 3 C except 4 to 6 C near Atlantic coasts.

At this time parts of northern England and eastern Scotland will have near-blizzard conditions as the low intensifies off the coast of eastern Scotland.

FRIDAY will be sunny and cold with isolated wintry showers, not as windy, lows near -3 C and highs near 4 C.

The outlook for next weekend is uncertain, cold air will try to hang on but could be quickly replaced in the south by milder air near 8 C and rain, leading to snow or sleet in parts of central and northern counties. There is also a slight risk of snow in the south on Saturday morning from a weak low expected to track south of Ireland into France.

That sort of pattern may repeat from time to time in the following week, with quick temperature changes as waves of low pressure move through Ireland from west to east in a rather active jet stream.

My local weather on Sunday was rather cold with a light snowfall in the early morning, followed by misty skies with glimpses of sun and temperatures steady around -4 C.

Wednesday, 20 January, 2021

Forecasts for Ireland


TRENDS for the week of 20-26 Jan 2021

-- Temperatures will average 2 to 3 deg below normal, falling into that range later today, then staying 3 to 4 below normal until about Monday night or Tuesday, with the rest of Tuesday milder. The week following looks quite variable and close to 1 or 2 deg above normal (that is 27 Jan to 2 Feb) but may end with colder weather.
-- Rainfalls or melted wintry precip will average about 50 to 75 per cent of normal, a little more today then rather dry to the weekend, some more mixed falls late Monday and rain on Tuesday. The week following that should be rather active for rain and possibly snow later into it.
-- Sunshine will eventually reach normal or slightly higher totals once today's cloud is gone.


FORECASTS

TODAY ... Colder air continues to press slowly southward and any parts of the southeast still above 8 C (when you read this) will soon turn colder also. Temperatures in most other regions are already in the 2 to 5 C range and will not gain much if any later today as the depth of cold air slowly increases. Any light rain falling in the colder air will eventually turn sleety and then to wet snow before ending this evening. Some parts of central and south Leinster could see slushy accumulations at lower elevations, of 1 to 3 cm by late afternoon; 5 to 15 cms of snow is quite likely on higher terrain in the southeast. Other parts of the country will have either mostly dry weather with a slow clearing trend, or isolated outbreaks of sleet perhaps only in drizzle form. Winds will continue rather light northerly (briefly moderate southwest in Wexford this morning) as storm "Cristoph" begins to assemble its various moving parts in the Irish Sea by later afternoon or evening. This low will develop much more rapidly between Manchester and Newcastle on its way to the North Sea off Scotland.

TONIGHT ... Partly cloudy west, overcast east, some further outbreaks of wet snow or sleet, quite cold, with moderate northerly winds picking up slowly but surely to reach 40 to 60 km/hr northwesterly by morning. Lows around -1 C except somewhat higher near north coast and some parts of the Atlantic coast.

THURSDAY will be breezy to windy at times with bands of mixed wintry showers developing especially around Donegal Bay and west of Galway and Clare ... these will push well inland moving a little south of due east, and dropping a wide variety of sleet, hail, wet snow and cold rain, partly separated out by elevation (snow will be most likely above 200m elevation, rain most likely near sea level). Highs 2 to 5 C inland, east and south coasts, but near 7 C on the west coast. Winds west-northwest 50 to 80 km/hr. Much stronger winds and heavy high terrain snowfalls are expected from storm Cristoph over in southern and central Scotland and parts of northern England, northwest Wales. There could be as much as 30-40 cms snow in places. The Dublin and Wicklow hills could see 5-15 cm additional, mountains in Ulster and Connacht could also see significant falls. Mountains further south will be more dependent on whether or not the sea effect bands happen to hit their vicinity or not. They could also get 5-10 cm falls if so.

FRIDAY will be a more sunny than cloudy day, still quite cold, but not as windy. There will be a few weaker bands of sea effect mixed wintry showers, turning readily to snow inland Ulster and Connacht, but making little further progress breaking up around the midlands. West Munster could also still see a few isolated wintry showers. Morning lows near -4 C and afternoon highs 2 to 5 C.

SATURDAY will be partly cloudy and there could be an interval of light snow in some areas, with coastal sleet, but this will come and go within a few hours, and other parts of the day will be brighter. Lows near -4 C and highs 2 to 5 C.

SUNDAY will also be partly cloudy and cold with more chances for light outbreaks of snow or sleet, lows near -5 C and highs 2 to 5 C.

MONDAY will be clear in the northeast with a sharp frost then eventually overcast like all other regions starting out, and a cold sleety rain or wet snow may develop by late in the day, lows -5 to -2 C and highs 3 to 7 C.

TUESDAY a frontal system may divide the country around Mayo to Meath, with areas north of that prone to mixed wintry sleet and wet snow, areas to the south a little milder with rain, highs 2 to 4 C north, 7 to 10 C south.

By mid-week more active disturbances are likely, and there could be further battleground scenarios with fronts dividing Ireland into colder north and milder south, but the boundaries may fluctuate further south at times, bringing sleety or snowy intervals as far south as inland Munster and south Leinster. One final push north around Thursday 28th may lead to a significant storm that I feel may not be entirely "visible" to the forecast models at this range.

The outlook beyond that is for a somewhat colder interval with some influence from high pressure in Scandinavia, southeast winds and mixed bands of precip likely. A very strong arctic high has pushed west to the north of Siberia for several days now and the models say it will drop southwest towards northern Russia but most of it will return to Siberia; however, a bubble of high pressure breaks away from it and tries to work closer to Sweden and Norway. This holds the key to any possible colder spells in February, and may interact with the stronger stages of the stratospheric events that are already underway. So we can't rule out a more severe wintry interval than any of the three relatively tame ones we will have seen by then.

My local weather on Tuesday was mostly cloudy but from higher layers well above the local peaks, so it was fairly bright despite all the cloud, and cold with highs around -5 C. Given the recent menu of weather, this means a lot of ice rather than slush on our streets and sidewalks, and tons of grit spread out to make them passable. I'm going to add a recent picture showing how much snow has accumulated here (about 60 cms) but at the same time, this is fairly normal and we lose track of it in town because wide areas are totally cleared of this snow (had to crouch down to take this picture and leave out the view of the cleared street).

Friday, 22 January, 2021

Forecasts for Ireland


TRENDS for the week of 22 to 28 Jan 2021

-- Temperatures will average 1 to 2 deg below normal, a blend of cold to around Monday (3-4 below average) and milder after Tuesday (2-3 above normal then).

-- Rainfalls will average near normal values and there may be significant amounts of snow in the precipitation.

-- Sunshine will average near normal values.


FORECASTS

TODAY will be partly cloudy with longer sunny intervals in the east than elsewhere, rather frequent mixed wintry showers feeding in from the west and northwest, changing readily to snow over higher parts of the north and west, but the snow line will also be falling to lower elevations by afternoon and evening. Winds west to northwest 40 to 70 km/hr, adding some chill to daytime highs near 4 C in most areas, 7 C near west coast.

TONIGHT will see some clear intervals developing, as wintry showers become confined to Atlantic coastal counties. Lows -4 to -1 C.

SATURDAY will start out clear and cold in many areas, then will become overcast with intervals of sleet or snow developing. These may become rather heavy across the midlands and parts of Munster and Leinster by evening and into the overnight hours, 5 to 15 cm snowfalls are possible although some lower elevations could see mixing and lose some of that total accumulation. Highs 2 to 5 C.

SUNDAY there may be a second wave of mixed wintry precipitation after some breaks in the overcast around mid-day and it will remain quite cold, lows near -2 C and highs near 4 C.

MONDAY will have some morning frosts and a slow increase in temperatures later in the day but as rain hits the west coast during the night it may turn to sleet or snow inland for a time until Tuesday morning, temperatures starting out below freezing (lows near -3 C) and rising to the 3-6 C range.

TUESDAY will turn slightly milder as rain pushes in slowly, turning sleet or wet snow over to rain eventually in parts of the inland north. Lows near 2 C and highs near 7 C.

The OUTLOOK for the rest of the week is milder with occasional rain and strong southwest winds; timing is a bit uncertain with a number of separate systems expected at roughly 24-36 hour intervals; the strongest of these now appears likely to be the "hidden low" I mentioned as models pick up the energy peak timed for about Thursday night into Friday.

Mild conditions may turn back to cold and snowy before the end of the weekend of 30-31 Jan, and the first week of February is looking rather cold in general with high pressure developing to the northeast, and winds turning easterly as a result. None of this is entirely "carved in stone" this far ahead, so stay tuned. This winter is probably far from done.

My local weather on Thursday was sunny and cold with highs (up at our elevation) near -4 C. Despite clear skies overhead we also had cap clouds over local hills, some of which were over low hills to our southeast that don't reach any higher elevations than right around here (a creek valley is in between), so that was an odd sight that I hadn't seen here in my brief residence.

Sunday, 24 January, 2021

Forecasts for Ireland


TRENDS for the week of 24 to 30 Jan 2021

-- Temperatures will average about 1-2 deg above normal, despite today and Monday being rather cold.
-- Rainfall will gradually accumulate to near normal values.
-- Sunshine will average 75% of normal.


FORECASTS

TODAY will continue cold with more outbreaks of snow, sleet and mixed wintry showers. Caution advised this morning for icy road conditions scattered throughout the country after overnight snow or mixed sleety precipitation. The most significant chance for further snow will come in Leinster this morning to around early afternoon, as an interval of north-northeast winds allows snow showers to develop near the coast and perhaps as far inland as the midlands at times. Some further accumulations of 2-4 cm are possible. This is not going to be a particularly well-organized event and results are likely to be "hit or miss" in nature. Elsewhere, more isolated snowfalls are likely but the trend in west Munster due to somewhat milder temperatures there will be more towards mixtures of rain, sleet and snow on hills. Highs today will range from about 1-3 C in the north and east, to 5-7 C in the southwest.

TONIGHT will become partly cloudy to clear at times especially over the inland southern counties where lows could fall to about -5 C. Further north, more cloud is likely with mixed wintry showers, some snow accumulations on hills in Ulster. Lows here will be closer to -1 C.

MONDAY will bring mostly cloudy skies and outbreaks of sleet or light rain, with slightly milder temperatures developing in most areas, highs 4 to 7 C.

TUESDAY will produce bands of wet snow, sleet and rain, all moving slowly north as warm fronts gradually overspread all regions. Highs 4-7 C in the north and 7-10 C south.

WEDNESDAY will be breezy to windy with intervals of rain and milder temperatures, highs near 11 C. Rain may become quite heavy at times by Wednesday night into early Thursday (20-40 mm rainfalls expected).

THURSDAY and FRIDAY appear likely to continue unsettled with strong winds at times and further rainfalls, possibly mixing with sleet in the north as colder air pushes some distance south. Highs will range from near 5 C in the north to 10 C in the south.

The OUTLOOK calls for the unsettled weather to continue with frontal boundaries quite likely to stall out in some northern or north-central counties, with much colder air not far away over eastern Britain during the last weekend of the month and into early February. Not too clear at this point whether the more likely outcome eventually is colder or continued "battleground" scenarios as the Atlantic does not show strong signals of yielding to the slow push of colder air from Scandinavia (which is dependent on a source region further east in Russia and ultimately Siberia).

My local weather on Saturday was overcast with a few patches of clear sky at times despite a lot of raggedy low cloud drifting around, and it continued rather cold with highs about -5 C.

Tuesday, 26 January, 2021

Forecasts for Ireland


TRENDS for the week of 26 Jan to 1 Feb 2021

-- Temperatures will average 1 to 2 deg above normal, although closer to average in the north.
-- Rainfalls will amount to 25% above normal values in some parts of the western and central counties, otherwise close to normal or a little below in some places.
-- Sunshine will average only 50% of normal and even that may be optimistic.


FORECASTS

TODAY will slowly turn milder, but rather cool air near the surface will persist for part of the day in the east and north, so that readings may stall at about 4-6 C there, further south, more easily reaching 8-11 C. Occasional rain will be heavy in a few parts of east Munster and later into the midlands. Further north it could mix with wet snow or turn to sleet at times, especially this morning.

TONIGHT will be foggy with light rain. The milder air will stop pushing north and so it will remain close to 4 C in parts of Ulster and north Leinster, while staying in the 6-8 C range further south.

WEDNESDAY will see outbreaks of heavier rain across central counties, and moderate to strong winds at times near the south coast (southwest 50-80 km/hr). Less windy further north, and still some tendency for cooler air to hang on near the surface in Ulster, keeping temperatures around 5 to 7 C there; otherwise highs will reach 10-12 C.

THURSDAY will turn slightly cooler with further outbreaks of rain, or sleet in the north, temperatures will settle back to around 7 C in the south and 3 C in Ulster.

FRIDAY will become colder with mixtures of cloud and sunshine, in northeast winds of 40 to 60 km/hr. Any precipitation is likely to be mixed and wintry but only small amounts are currently indicated despite that wind direction, the air mass seems a bit too stable to produce much shower activity. Highs will be 3 to 7 C.

SATURDAY could stay fairly cold and there's a slight risk of sleet or wet snow in a few spots, although once again, guidance is leaning towards a dry and stable air mass that will eventually begin to yield to milder air by the overnight hours. Highs once again 3 to 7 C.

SUNDAY and MONDAY another mild spell looms with rain or drizzle, potential for about 10-20 mm rainfalls each day. Highs 8 to 11 C.

By TUESDAY (2nd Feb) it may begin to turn colder in stages and some guidance is more aggressive with this colder trend, if that guidance is correct there may be some localized snowfalls as early as mid-week. However we are into one of those slow motion advances of colder Russian air masses into northern Europe that can confuse the models for days on end, so the basic theme is going to be waiting for clearer indications of a colder spell that seems quite likely to come some time in early to mid February.

My local weather on Monday was overcast and rather mild compared to the previous few days, with highs just under the freezing mark, and a skiff of new snow (less than 1 cm) in the morning. Colder air seems likely to push back in here soon though, as we're just in the weak and almost collapsed milder sector of a very weak low that dropped in between pulses of arctic air. On the hemispheric charts, there is strong high pressure now close to the North Pole and it connects to several other highs in Greenland, north-central Canada, and central Siberia. This has the effect of keeping weather patterns stagnant, since this polar high anchors any other cold weather regimes that might otherwise be on the move.

Thursday, 28 January, 2021

Forecasts for Ireland


TRENDS for the week of 28 Jan to 3 Feb 2021

-- Temperatures will average near normal.
-- Rainfall will average 75 to 100 per cent of normal.
-- Sunshine will average 50 per cent of normal, possibly less in the south, a little better in Ulster.


FORECASTS

TODAY will start out mostly cloudy with any remnant drizzle in the north gradually ending, otherwise, dry to mid-day or early afternoon for many, then intervals of light rain, and gradually increasing southwest winds in the south coast counties (less windy further north). Highs 8-11 C except 4-7 C in the north.

TONIGHT will see a few further outbreaks of light rain and the moderate southwest winds 50-80 km/hr will gradually ease near the south coast, lows 4-7 C.

FRIDAY will have a few dry intervals, as winds turn more southeast to easterly, then rain will arrive again in the south, west and central counties, spreading to Leinster by late afternoon or early evening. This rain could start to change over to sleet or wet snow on high ground because somewhat colder air will be gradually feeding into the rainfall but closer to the south coast it will remain 8 or 9 C and 15-30 mm rain can be expected there. Temperatures further north may slowly fall off to around 5 C at lower elevations, 2-4 C on higher ground.

SATURDAY some rain will continue mixed with sleet or wet snow on higher ground in some parts of the south; it will likely be dry but mostly cloudy with a few brighter intervals further north. Temperatures will vary from 7 C in the south to 2-5 C in the north.

SUNDAY another weak system will try to push the colder air back to the north but it may take until Sunday night before there is much change in the frontal zones, so that a cold rain in the south may trend more towards sleet or wet snow in central counties and if it reaches far enough north, measurable snowfalls are possible in south Ulster. Temperatures will remain around 4 to 7 C for most, 2 to 5 C north, and 10-20 mm rain or liquid equivalent can be expected.

MONDAY the milder air may have one last attempt to push north, and may succeed briefly but then the system will weaken and colder air will seep back into the north later in the day. Some rain at times with fog likely, highs near 7 to 9 C in the south, 3 to 6 C north.

By TUESDAY a somewhat cooler easterly flow will develop, and this could have some mixed wintry showers although it looks fairly settled, with highs near 5 C.

The pattern for the rest of next week looks rather cloudy with east winds and perhaps a few more minor skirmishes in the south between somewhat milder air and the gradually dominating colder air. This could lead to a few intervals of sleety rain or wet snow. However, the big weather story may be what happens towards the end of next week, as most guidance seems to be tracking similar outcomes with much colder air settling into northern Europe and then gradually extending its influence over most of Britain, with Ireland perhaps in line for a visit too by about Sunday 7th February, and if so this could be quite a cold interval with snowfall potential especially near the east coast. By no means is this certain to happen (based on usual model reliability, about a 60-70 per cent chance however).

My local weather on Wednesday was overcast with snow, which was heavier in the first half of the day and amounted to nearly 20 cms of light powder, it shovelled more like 10 cms so must have been moisture deficient. Temperatures were about -3 C through the snowfall. The east coast of the U.S. is about to turn very cold with a small disturbance bringing 5-10 cm snowfalls to North Carolina and southern Virginia late tonight (local time) then a stronger storm is expected from the central plains states by Sunday night and this could bring 15-30 cm snowfalls to the larger cities from Washington DC to Boston during Monday and Tuesday. The first low bringing some snow tonight will explode into a very powerful storm over the Atlantic but it looks set to miss Newfoundland as it curves up towards southern Greenland. It will be a hazard for shipping with winds reaching 160 km/hr south of Nova Scotia on Friday.

Saturday, 30 January, 2021

Forecasts for Ireland


TRENDS for the week of 30 Jan to 5 Feb 2021

-- Temperatures will average near normal in the south to 2 deg below normal in the north.
-- Rainfall will average 50% above normal in the south, trending to near or slightly below normal in the north. Larger portions of the precipitation will be in wintry precip forms further north too.
-- Sunshine will average 25 to 50 per cent of normal.


FORECASTS

TODAY will be a raw, windy and wet day in most central counties, and somewhat milder but foggy or drizzly near the south coast. Some of the rain in Leinster could begin to mix with wet snow towards the end of the event mid-day, as colder air mixes in from Britain. Temperatures currently near 5 C in central counties will drop slowly to the 2-4 C range later, and readings 8-10 C near the south coast will fall off slightly also. Ulster and some parts of adjacent regions will escape most of this wintry mixed fall today and could even see some partly cloudy intervals. Winds for all regions will be rather strong east to northeast 50 to 80 km/hr adding quite a chill, not a day you would want to be outside for very long in central counties. About 20-30 mm rainfalls will be total amounts including what has already fallen (in many places about half of that).

TONIGHT will have some clear intervals and a frost in many areas, lows -3 to +1 C. Winds not as strong but still fairly moderate from northeast to east at 30-50 km/hr.

SUNDAY will see a weaker disturbance trying to push along the same frontal boundary which by morning will have slumped a bit further south. This means that a mixture of snow, sleet and rain will begin to fall in Connacht and possibly Clare (inland) before spreading into the midlands by mid-day. Current guidance suggests it won't extend quite as far as Dublin before changing to a cold rain, but probably on higher terrain in Leinster the mix will continue, as temperatures are not likely to come up much from the morning lows. Highs for the day only 3-5 C and that could be during dry intervals, with the precipitation temperatures may be fairly close to 1 C. Not as windy as today but some moderate east winds at times.

MONDAY to WEDNESDAY the guidance generally suggests that a slight Atlantic influence will continue despite the gradual massing of very cold air over northern latitudes of the Atlantic and most of Scandinavia. Even so, some of the rather frequent light rain expected in this first part of the week could easily change over to sleet or snow in parts of the north and on higher terrain, with temperatures generally in the range of 4 to 7 C for most places, and 2 to 5 in the north and on higher terrain. Each day will likely have some intervals of light rain, fog and drizzle, with winds generally rather light as disturbances weaken upon approach from the west. Some intervals of stronger winds could develop near the south coast as these lows die out over Ireland and later south-central Britain or northern France.

From THURSDAY to SATURDAY the guidance generally suggests that Ireland will be on the margins of a large outbreak of colder air with east to northeast winds. Some guidance says that temperatures will fall to very cold values as far west as Ireland, while other guidance limits the spread of this arctic air to eastern England and leaves the frontal zone somewhere near Wales. The latter is of course more likely than not whenever this split is suggested, but the colder guidance is quite robust in appearance so I am calling this a 50-50 proposition, whether or not Ireland gets into the coldest part of this developing arctic northeasterly outbreak. If Ireland does get in, some significant snowfalls are quite likely in Leinster especially. If not, then temperatures will remain in the 4-7 C range like the first part of the week, with drizzly light rain at times.

Around SUNDAY 7th to TUESDAY 9th there seems to be an even greater chance of the coldest air reaching Ireland and this would be the most likely time then for a wintry episode of subfreezing temperatures and snowfalls. But it is by no means "carved in stone" that it would actually become that cold.

Longer term in February, there are signs of further battles between the Atlantic and polar origin arctic air masses with some maps wanting to connect up all known sources of cold air into one gigantic pool of very cold air that would make February quite extreme. I find the parallel to Feb 1895 interesting because at the same time guidance is showing severe cold outbreaks in eastern North America and this combination happened in both that year and 1855, as well as 1917 to a slightly lesser extent. (1917 is remembered in Ireland for a massive snowfall that happened at the end of March and into early April). So let's say this winter has "form" but that alone is no guarantee of an outcome, in more recent decades of course the tendency has been for promising cold to push to the doorstep and then back away (this happened a few times in Feb 2013 before a cold March interval developed, it also occurred in other winters around then).

I like to give you the probabilities rather than just picking A or B and hoping to be right on a coin toss. So you may hear different things from other sources who have decided to go with one or another of these possible outcomes.

My local weather turned a bit milder which softened up our recent heavy snowfall accumulations, without doing much melting of it, with temperatures that edged up to around 3 C. We are expecting another 15-30 cm snowfall tonight and Sunday which is going to make for some interesting photos by middle of next week. We found a place nearby with an undisturbed winter snow pack that measured 85 cms. Now that is not present all over the town, it varies from 50 to 100 cms and then a lot of organized snow clearance takes place leaving some areas almost devoid of snow. After this next dump of snow we could be close to or over one metre around here.

The east coast of the U.S. will get a heavy snowfall from Sunday to Tuesday, model predictions are over a fairly wide range but they all have some places getting two feet of snow, the most likely snow jackpot seems to be eastern PA, northeast MD and most of NJ, but anywhere from about southern Virginia to Maine could see heavy amounts. This may prove prophetic or not, but the models showing the most snow are also showing the deepest cold over Ireland, so I'll keep an eye on how that coupling unfolds and whether it proves predictive or just a background noise factor of no consequence.

Just for interest, the degree of cold at present time (as shown for Ireland in 7-10 days) ranges from most extreme on the Canadian model, to medium extreme values on the U.S. (GFS) model, to weak on the European model. However a day or two ago the European model was showing a more robust cold solution and might return to that, plenty of time for models to "chop and change." The feature that seems to be giving the models difficulty is a strong high pressure area near the north pole that is gradually extending towards the Russian side, but some guidance has it pushing towards western Russia and Scandinavia, other sources say central to eastern Siberia. This seems to be making a large difference in the output for Europe.