[M.T. Cranium]

Important: Please note legal disclaimer published once a month, can be seen at bottom of post 2565 dated 24 July 2012.

Friday, 10 August, 2012
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Forecasts for Ireland

TODAY ... Patchy morning cloud or mist, then hazy sunshine for most places, very warm or hot with highs 23 to 27 C. East coast slightly cooler near the shore, south coast may stay in the low cloud and fog much of the morning but could clear at times to warmer sunshine later, highs 19-22 C. Some high cloud will be dimming the sun at times in the afternoon in west, but strong sunshine in many parts could burn in 20-30 mins without protection.

TONIGHT ... Some clear intervals, especially over higher terrain, low cloud and drizzle may spread inland across south with light rain in parts of Kerry, Cork, Waterford (trace to 2 mms). Lows about 12 C on average. Moderate southeast winds developing in southern counties, rain spreading slowly towards southeast counties by early morning hours.

SATURDAY ... Somewhat cooler especially in south and southwest, outbreaks of light rain in west Munster, slight risk of thunderstorms developing west-central to southeast along a slowly advancing (to northeast) front. Rainfalls of 5-10 mms in some parts of Munster, south Leinster. Continued rather warm in Ulster, east Connacht and north Leinster, with highs 22-25 C in north, 18-22 C central, but only 15-17 C south and southwest.

SATURDAY NIGHT may also have some clear intervals with lows 8-11 C in eastern and northern counties as the push of cooler air may become quite weak, the front could begin to dissipate before redeveloping on Sunday. In general, I would say the chances of clear skies are about 60% on Friday night and 40% on Saturday night in the region near Dublin where observers might be most interested in viewing the Perseids. Sunday night is more likely to be extensively overcast.

SUNDAY ... Becoming mostly cloudy, extensive showers or thunderstorms possible, although there may be some places with warm sunshine also. Winds having backed into the southeast may now begin to return to southerly, highs around 21 C in some places, 15-17 C closer to south and west coasts.

MONDAY to WEDNESDAY ... Showery with some intervals of heavier rain possible, also a risk of strong SW winds developing with a small but intense low indicated on some model charts moving north to northeast across western counties around Tuesday. Temperatures will remain rather mild especially at night (typically lows near 12 C and highs near 17 C).

FURTHER OUTLOOK ... The longer term looks relatively warm again, and it's possible that all periods will turn out a bit warmer as the push of cool Atlantic air may be rather weak this time. However, I still think that there is also some chance of a full return to the drab conditions of mid-July. Have seen a few charts in about two weeks that look warm to hot again, so perhaps this month will be a departure from recent years after all.


Forecasts for Britain

TODAY ... I should have mentioned fast moving bolts for Thursday but today is likely to be hot in most places, with any morning cloud or mist rapidly giving way to almost clear skies, just the usual slight cooling near some coasts and in the far north. For almost all other locations in Britain, expect highs 27-32 C and light winds. Some east coast fog and highs 20-23 C.

TONIGHT ... Hazy, becoming misty or foggy and close, lows 15-18 C. This will trend to cooler, clear conditions in parts of the inland north with lows 8-12 C in some valleys. Dense fog could develop especially close to east coast.

SATURDAY ... Increasing cloud west, some late showers or isolated thunderstorms, highs 23-27 C. Sunny again in the east until quite late afternoon or evening, hot with highs 27-30 C. Isolated heavy or severe evening thunderstorms may move north from France. (by the way Friday-Saturday in northern France could reach 35 C).

OUTLOOK ... Staying hot over the weekend in southeast England, showery further west with some heavy thunderstorms developing by Sunday in areas like Bristol and Bournemouth, Salisbury plain, Thames valley; turning a bit cooler especially west of London to Nottingham, but much of next week could stay a little warmer than average with highs 22-24 C. Heavy rains likely at times in Wales and Scotland, northern England mid-week.


North American forecasts

Heavy rainfalls continuing in parts of the lower Great Lakes and inland northeast, 30-60 mms could be recorded in places. Fairly dry in central regions with seasonably warm temperatures, trending to hot further west. Scattered but isolated thunderstorms over Rockies and parts of western Canada. Very hot in the southwest trending to near normal in coastal California due to strong sea breezes. Ernesto will slowly die over Mexico while dropping torrential rains. "Gordon" could form later today or Saturday near Cape Verde, heading for the Caribbean in 4-5 days. Florence came and went without doing much, a remnant low is north of Puerto Rico.

MTC's LOCAL WEATHER (Thursday) was sunny and warm, highs near 23 C. About the same as Galway as it turned out.

[M.T. Cranium]

Important: Please note legal disclaimer published once a month, can be seen at bottom of post 2565 dated 24 July 2012.

Saturday, 11 August, 2012
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Forecasts for Ireland

TODAY ... Somewhat cooler especially in south and southwest, outbreaks of light rain in west Munster, isolated showers elsewhere, followed by a slight risk of thunderstorms developing west-central to southeast along a slowly advancing (to northeast) front. Rainfalls of 5-10 mms in some parts of Munster, south Leinster. Continued rather warm in Ulster, east Connacht and north Leinster, with highs 19-23 C in north, 18-22 C central, but only 15-19 C south and southwest. There may be a slight clearance in the southwest this afternoon. Will be watching for potential of severe thunderstorm alert after about 2 p.m., for now would say 10-20% chance.

TONIGHT, although mainly cloudy, may have some clear intervals with lows 8-11 C in eastern and northern counties as the push of cooler air may become quite weak, the front could begin to dissipate before redeveloping on Sunday.

SUNDAY ... Becoming mostly cloudy, extensive showers or thunderstorms possible, although there may be some places with intervals of warm sunshine also. Winds having backed into the southeast may now begin to return to southerly, highs around 21 C in some places, 15-17 C closer to south and west coasts. Heavier rain likely by evening and overnight with some thundery showers embedded, amounts of 10-20 mms by Monday morning.

MONDAY ... Showery with some intervals of heavier rain possible, then becoming partly cloudy, lows near 12 C and highs 18-20 C.

TUESDAY ... Variable cloud, showers, mild. Lows near 11 C and highs 19-21C.

WEDNESDAY ... Periods of rain becoming heavy, 20-40 mms potential, winds also increasing to E-SE 20-40 mph as low pressure approaches from south to southwest. Lows around 10 C and highs around 17 C.

OUTLOOK ... Slight improvements later in the week, staying rather unsettled through next weekend, and then chance of another warm spell developing in the following week (19th to 23rd).


Forecasts for Britain

TODAY ... Increasing cloud west, some late showers or isolated thunderstorms, highs 23-27 C. Sunny again in the east until quite late afternoon or evening, hot with highs 27-30 C. Isolated heavy or severe evening thunderstorms may move north from France, slight chance of them arriving near the end of the day in London and region.

TONIGHT ... Variable cloud, mild to warm, outbreaks of rain mostly west and just a few showers in eastern sections with the risk of one or two heavier thunderstorms. Lows 14-19 C.

OUTLOOK ... Sunday and much of next week could stay a little warmer than average with highs 22-24 C. Sunday is likely to be mostly cloudy with scattered showers and a few thunderstorms. Heavy rains likely at times in Wales and Scotland, northern England mid-week. The weather has certainly co-operated with the two week interval of the Olympic Games.


North American forecasts

Slow-moving frontal bands of heavy showers continue to plague the northeast U.S. and eastern Great Lakes, with gradual clearing further west. Hot and dry across most of the west today. Scattered daytime storms over higher terrain in southwest.

MTC's LOCAL WEATHER (Friday) was sunny, hazy and a bit cooler due to a stronger sea breeze today with highs near 20 C.

[M.T. Cranium]

Important: Please note legal disclaimer published once a month, can be seen at bottom of post 2565 dated 24 July 2012.

Sunday, 12 August, 2012
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Forecasts for Ireland

TODAY ... Mostly cloudy, extensive showers or thunderstorms possible, although there may be some places with intervals of warm sunshine also. Winds having backed into the southeast may now begin to return to southerly, 20-30 mph at times, with highs around 19 to 21 C in some places, 15-17 C closer to south and west coasts. Heavier rain likely in bursts this morning across the east mainly, and then again by evening and overnight in various places with some thundery showers embedded in both periods, amounts of 10-20 mms by Monday morning and potential for 10-20 mms in either or both of these intervals, so that one or two places could see spot flooding briefly.

TONIGHT ... Heavy showers passing through then foggy, very mild, lows 11-14 C.

MONDAY ... Showery with some intervals of heavier rain possible, 15-30 mms potential, embedded thunderstorms, then becoming partly cloudy, lows near 12 C and highs 18-20 C. Winds veering more to southwest then slackening by evening.

TUESDAY ... Morning mist or fog, some sunshine at times later with variable cloud, showers, mild. Lows 8 to 11 C and highs 19-21 C.

WEDNESDAY ... Periods of rain becoming heavy, 20-40 mms potential, winds also increasing to E-SE 20-40 mph as low pressure approaches from south to southwest. Lows around 10 C and highs around 17 C. An alert will probably be added to the forecast by Monday morning if this scenario holds together, although frankly each day from now to then looks borderline alert status in some places, so it's more of a case of back to the earlier summer pattern for a while (although perhaps warmer).

THURSDAY-FRIDAY ... Cloudy, a bit cooler, fresh SW to W breezes, showers. Highs around 16-18 C.

OUTLOOK ... Slight improvements later into the weekend, staying rather unsettled through early next week, and then chance of another warm spell developing later in the following week (20th to 23rd).


Forecasts for Britain

TODAY ... Variable cloud west, passing showers and a few thundery ones, heavier in Wales and later southwest Scotland, northern England. More isolated showers central England and likely to remain largely dry if cloudy at times southeast. Highs will range from 17-20 C west, north, to 22 C central to 25 C southeast.

TONIGHT ... Showers becoming heavier, some with thunder, a few parts of the south and southeast could remain dry, very mild in southerly winds of 20-40 mph, lows 14-18 C.

OUTLOOK ... Much of next week could stay a little warmer than average with highs 22-24 C. Rainfalls will be heavy in parts of west and north, moderate central and possibly continuing rather dry in the southeast although not totally so.


North American forecasts

Little change due to very slow motion of systems, so as per yesterday, slow-moving frontal bands of heavy showers continue to plague the northeast U.S. and eastern Great Lakes, with gradual clearing further west. Hot and dry across most of the west today (added, getting warmer by several degrees in parts of western Canada, to near 30 C). Scattered daytime storms over higher terrain in southwest and northern prairies.

MTC's LOCAL WEATHER (Saturday) was sunny, and a bit warmer again with highs near 23 C. We are now having a reasonably average sort of mid-summer here, nothing exceptional, it often stays dry for about 4-6 weeks here when the Pacific highs start swelling up. The hottest temperatures ever recorded here were at the end of July 2009 when it hit 35 C at YVR (which is near the ocean) and unofficially about 38 C at my location 10 kms further inland, that being on the 29th and again 30th. The coldest reading in the past century here was -18 C in January 1950. So the extremes are about the same as most places in rural central England, I would say, or the absolute extremes in Ireland (almost).

[M.T. Cranium]

Important: Please note legal disclaimer published once a month, can be seen at bottom of post 2565 dated 24 July 2012.

Monday, 13 August, 2012
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ALERT for heavy rainfalls and intense lightning in north-central counties spreading into parts of Ulster and north Leinster, tending to weaken after mid-day, 20-30 mms rain and spot flooding may result ... ADVANCE ALERT for strong winds and heavy rainfalls Wednesday (see forecasts for details).

Forecasts for Ireland

TODAY ... Very humid with thundery showers north-central, spreading to east and north to cover much of Ulster and north Leinster, inland Connacht, 20-30 mms rain in some places, intense lightning, spot flooding. Partial clearance to follow, warm sunshine at times, then outbreaks of showery rain, embedded thunderstorms, a further 10-15 mms in some places later today. Highs 18-21 and winds SSW 20-35 mph. then becoming partly cloudy, lows near 12 C and highs 18-20 C.

TONIGHT ... Cloudy intervals, fog, a few showers although some places dry, lows 10-13 C.

TUESDAY ... Morning mist or fog, some sunshine at times later with variable cloud, showers, isolated thunder and warm, highs 19-21 C.

WEDNESDAY ... Periods of rain becoming heavy, 20-40 mms potential, winds also increasing to E-SE 20-40 mph as low pressure approaches from south to southwest. Lows around 10 C and highs around 17 C. Winds rapidly veering to SW 30-60 mph with the higher gusts mainly around southwest coast mid-day and northwest coast later afternoon. This situation will probably require frequent updates as the system is small but powerful (in theory).

THURSDAY-FRIDAY ... Cloudy, a bit cooler, fresh SW to W breezes, showers. Highs around 16-18 C.

WEEKEND OUTLOOK ... Variable cloud, isolated showers or more frequent showers in some western counties, near average temperatures (18-20 C).

FURTHER OUTLOOK ... Next week could see somewhat warmer temperatures again with some dry spells returning. Highs could reach 22-24 C.


Forecasts for Britain

TODAY ... Mostly cloudy west, passing showers and a few thundery ones, heavier in Wales and later southwest Scotland, northern-central England. More isolated showers east-central England and likely to remain largely dry if cloudy at times southeast. Highs will range from 17-20 C west, north, to 22 C central to 25 C southeast.

TONIGHT ... Showers and a few thunderstorms, mainly in west and north, partly cloudy further east, mild in southerly winds 20-40 mph, lows 13-17 C.

OUTLOOK ... Much of next week could stay a little warmer than average with highs 22-24 C. Rainfalls will be heavy in parts of west and north, moderate central and possibly continuing rather dry in the southeast although not totally so. Strong winds spreading from Ireland to western Scotland and Wales late Wednesday, some gusts to 70 mph possible in Hebrides.


North American forecasts

Showery east coast, and also west-central Great Lakes to Mississippi valley, with some dry and warm conditions in between around Ohio and western PA, southern ON and w NY. Hot and dry most of the central and western regions, with a few heavy storms moving east through Alberta into Saskatchewan. Sunny and seasonably warm near west coast.


MTC's LOCAL WEATHER (Sunday) was sunny and hazy, highs near 25 C.

[M.T. Cranium]

UPDATE _ Mon 13 Aug 2012 _ 7:10 p.m.

ALERT for heavy rainfalls locally east Galway, south Roscommon, nearby portions of other counties, now to 8:30 p.m., 20-30 mms and brief spot flooding on roads.

ADVANCE ALERT now upgraded to 75% chance storm force wind gusts and some isolated sustained winds of 50-70 mph 50% chance of isolated hurricane force wind gusts (75-85 mph) mainly south and west coast regions, possibly exposed areas east, inland central and north also. This situation will be reassessed at 0630h from later guidance. Current model runs are showing the potential for an intense depression to form Tuesday night south of Valentia moving due north into western counties. The region around Cork is especially at risk for damaging winds and local tidal-flooding issues as the date will not be far off new moon.

More discussion likely in forum thread, your ob'dt servant now off duty to midnight IST.

[M.T. Cranium]

Important: Please note legal disclaimer published once a month, can be seen at bottom of post 2565 dated 24 July 2012.

Tuesday, 14 August, 2012
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ALERT for storm force winds with hurricane force gusts in exposed locations and very heavy rainfalls sweeping north tonight and lasting much of tomorrow, with some blustery squalls embedded. Potential for wind gusts to 80 mph in the most exposed coastal and upland locations, 60 mph more widely ... potential for 30-40 mms rainfall with severe flood risk where soils now saturated from previous rainfalls. More details in forecast.

Situation: A very powerful summer storm appears likely to develop explosively tonight as a deep vortex in the upper atmosphere rotates from its current location in the central Atlantic towards Biscay then north towards Valentia. A deep surface low that could reach 968 mbs is likely to develop very rapidly after midnight in response to this vortex (a swirl of colder air) slamming into the warm, humid air mass now present. The track of this low will be approximately due north across Kerry or near Valentia, up the west coast veering more to the northwest after passing Galway Bay mid-day Wednesday. The low will remain intense but will pull rapidly away from Ireland in the afternoon, leaving Mayo in the wake of diminishing southwest gales. Wind speeds should both rise and fall off rather swiftly during various phases of the low's brief rampage. All regions will be exposed to strong gusts although the highest wind speeds could be expected near Cork and various exposed locations. It would be very dangerous to be hiking above sheltered areas anywhere on Wednesday but fortunately this should become obvious before daylight. If you know of anyone with plans to set out today and camp, or anyone who left earlier on such an outing, they should be contacted and warned to return to shelter. Marine areas will see hurricane force wind gusts to force 11-12 and sailing after about 9 p.m. tonight is strongly discouraged. Persons living in hilly areas of the southwest should think back to a similar storm in January 2010 and assess possible wind damage risks from channelling of SSE winds pulled through gaps in the terrain.


Forecasts for Ireland

TODAY ... Morning mist or fog, some sunshine at times later with variable cloud, showers, one or two with thunder or hail, local rainfalls 10-20 mms although many places 2-5 mms, and warm, very humid, highs 18-21 C.

TONIGHT ... Becoming stormy in the south with winds rapidly increasing to ESE 30-50 mph, gusts to 70 mph in exposed locations by early morning, and driving rains giving 20-40 mms by morning. The Cork region may see flooding risks from both rainfall runoff and rising tides. This could become the case further east also. Rain will reach central regions after midnight and the north by about sunrise. Winds will also increase rapidly there, reaching SE 25-45 mph with some higher gusts in exposed locations. Rainfalls for these regions incorporated into following day forecast, but about 10 mms by dawn.

WEDNESDAY ... Periods of rain becoming heavy, 20-40 mms potential for most but 30-50 mms locally, severe local flooding where ground saturated from previous rain. Winds across the south will peak during the morning or mid-day from a SSE direction, reaching 40-70 mph and gusting to near hurricane force at times. There is potential for moderate structural and tree damage. Very exposed higher terrain could see gusts to near 100 mph. Around the southeast and east coasts and well inland, winds will rise to about SE 30-55 mph and will veer rapidly to SW 30-50 mph. Some squally showers or storms could develop along the windshift and the risk for local tornadic wind streaks will be monitored, especially valid around Limerick and Tipps north into the Athlone district. Connacht will see a more gradual increase in wind speeds all morning to reach SSE 40-60 mph and then a gradual turn to SSW 40-60 mph with higher gusts possible. Ulster may be somewhat protected from the strongest winds and will see wind speeds of about 30-50 mph. There could be some brighter or even sunny intervals later in the day across the southwest and the storm may rapidly subside to more of a partly cloudy, isolated showers scenario with winds SW 20-40 mph. Highest temperatures will be 16-18 C for most, 18-20 C in parts of southwest and north Donegal (Malin Head could hit 22 C).

WEDNESDAY NIGHT ... Further improvements are expected to clear spells, passing showers, winds SW 15-30 mph although 25-55 mph in the northwest, and lows 10-12 C.

THURSDAY-FRIDAY ... Cloudy, a bit cooler, fresh SW to W breezes, showers. Highs around 17-21 C.

WEEKEND OUTLOOK ... Variable cloud, isolated showers or more frequent showers in some western counties, near average temperatures (18-22 C).

FURTHER OUTLOOK ... Next week could see somewhat warmer temperatures again with some dry spells returning. Highs could reach 22-24 C.


Forecasts for Britain

TODAY ... Mostly cloudy, a few showers, one or two isolated thunderstorms in Wales and western England. Mild to warm, highs 19-23 C, southerly breezes at 15-30 mph. Rather humid and brief sunny breaks for some.

TONIGHT ... Showers and a few thunderstorms, rising southeast gales for parts of southwest England and Wales, breezy further east, warm with lows around 14-17 C.

WEDNESDAY ... The severe storm will largely brush past most of Britain with peak gusts around 60 mph in Cornwall and parts of Wales. The wind direction will remain SE for most places and a line of squally showers or thunderstorms will try to push east through Wales and about Somerset-Dorset but may not make it too much further east before fragmenting. Highs about 22-25 C east of that front all the way up into Scotland, closer to 18-20 C where the front does manage to move through.

OUTLOOK ... The second half of the week could stay a little warmer than average with highs 22-24 C. Rainfalls will be heavy in parts of west and north, moderate central and possibly continuing rather dry in the southeast although not totally so.


North American forecasts

Most places seasonable and just a few isolated regions with showers or thunderstorms, eastern Canada, parts of B.C. and Alberta, and the inland southwestern U.S. are all in line for a few heavy or locally severe storms, but many other regions will be dry and seasonably warm to hot.

MTC's LOCAL WEATHER (Monday) was sunny and hazy despite a lot of higher cloud, and it was borderline hot and a bit humid for this location with highs near 28 C. Storms are developing northeast of here now and a cooler push of marine air seems to be developing for Tuesday morning here.

Updates as necessary on the impending storm, and lots of discussion in the forum threads.

[M.T. Cranium]

Update ... Tues 14 Aug 2012 ... 2015h
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ALERT maintained for dangerous storm conditions likely to set in across the south late overnight and during the morning rush hour period, spreading more rapidly north after 0700h to overspread much of Ireland. Parts of Ulster may be spared significant impacts, but otherwise, expect very strong winds and heavy rainfalls with the usual variations due to exposure. Forecast details are updated below. A continuous watch is now underway, further updates only if this scenario requires substantial alterations.

TONIGHT ... Starting out relatively benign with variable cloud, passing light showers and a slowly rising SE wind at about 15-30 mph by midnight and then rising rapidly in the south coast regions to 40-60 mph with heavy, driving rain about 0500-0700h. Lows 14-17 C.

TOMORROW ... Strong winds and very heavy rainfalls rapidly spreading north to cover most of Ireland, less severe in Ulster. Winds near south coast slowly veering to SSW 50-80 mph with severe and possibly damaging gusts. East coast staying longer in SE winds at 40-60 mph. Rainfalls 30-50 mms, potential for higher amounts in upslope areas facing south-east. Highest temperatures 15-18 C except 20 C Ulster.

Connacht and central counties of Ireland are likely to see a more gradual rise in wind speeds during the day peaking around late afternoon or evening SSE 30-55 mph with locally higher gusts.

1900h storm location is approx 44N 16W heading NNE, current central pressure estimated 995 mbs, to be around 975 mbs at 50N 12W by 0600-0900h and near or just west of Valentia 972 mbs by 1500 to 1800h. Storm likely to track NNW after that veering to NW after midnight, maintaining a similar central pressure. The swerve away from Galway-Mayo would be the only reason why peak gusts there later on will not equal those in Kerry, Cork and Waterford mid-day. Clare and Limerick can also expect some very strong gusts.

NEXT UPDATE LIKELY AT 0100h. My intermediate thoughts to be found in forum thread on storm. Will post tracking info as storm quite likely to pass K1 buoy at 2300h (location approx 49N 12.5W)

[M.T. Cranium]

UPDATE ... Wed 15 Aug 2012 ... 00:45h

No major changes in forecast. Storm appears to be rapidly developing now around 46.5N 14.5W and heading northeast. Considerable lightning detected in frontal band near 47N 11W. This may translate into morning thunderstorms embedded in bands of heavy rain across south-central counties.

Stormy conditions can be expected to hit the outer south coast 0400-0500h and Cork, Waterford cities 0500-0600h. From there, the front edge of the storm will accelerate and reach a Shannon to Wicklow arc about 0800h and Galway to Dublin 0900h (onset approximate as some squally showers may break out ahead of front edge).

Rain seems likely to persist all day in most places, once started, and the first signs of abatement will be southwest of Cork around late evening. Strongest winds are still expected early to mid afternoon on the south coast. See previous alert(s) for all other details.

Next update around 0330 to 0400h.

[M.T. Cranium]

UPDATE _ Wed 15 Aug 2012 _ 0400h
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Data confirm that explosive development of storm has occurred, current location of centre appears to be 48N 13W approaching K1 buoy where pressure is falling rapidly and winds increasing. This buoy is always rather conservative on wind speeds so 29 knots sustained is on course for the later forecast. Central pressure is probably about 980 mbs now and continues to fall. Upper air guidance show that the expected deep vortex has formed just to the west of the surface centre. This phasing "bomb cyclone" will now move towards southwest Ireland with an intensity similar to a 45-kt tropical storm. Satellite presentation is impressive and enough land-based radar now catching the front to suggest heavy rain forecasts will verify.

Forecasts remain unchanged awaiting further model guidance.

[M.T. Cranium]

Important: Please note legal disclaimer published once a month, can be seen at bottom of post 2565 dated 24 July 2012.

Wednesday, 15 August, 2012
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ALERT for storm force winds with hurricane force gusts in exposed locations and very heavy rainfalls sweeping north today, with some blustery squalls embedded. Potential for wind gusts to 80 mph in the most exposed coastal and upland locations, 60 mph more widely ... potential for 30-60 mms rainfall with severe flood risk where soils now saturated from previous rainfalls. More details in forecast.

Situation: A very powerful and unusual summer storm has developed explosively overnight as a deep vortex in the upper atmosphere approaches southwest Ireland. A deep surface low that could reach 972 mbs is currently located about 200 miles south-southwest of Valentia with central pressure about 976 mbs. This will now track almost due north to a point just west of Valentia by 1300-1400h and then up the west coast veering more to the northwest after passing Galway Bay late afternoon Wednesday. The low will remain intense but will pull rapidly away from Ireland in the evening, leaving Mayo in the wake of diminishing southwest gales. Wind speeds should both rise and fall off rather swiftly during various phases of the low's brief rampage. All regions will be exposed to strong gusts although the highest wind speeds could be expected near Cork and various exposed locations around the south and east coasts as well as certain inland locations that can channel winds effectively from an ESE to S direction. Hiking above 300m today is strongly discouraged in all regions, the storm will gradually set in by mid-day across the north too. Marine areas south and later west will see hurricane force wind gusts to force 11-12 falling off to 8-10 later, while the Irish Sea will peak around force 9-10 falling off to 5-7 later, so that sailing is strongly discouraged. Waves could overtop shoreline installations around high tide on the south coast, should be a bit less severe on the east coast, but the west coast will have a "chaotic" sea state due to rapidly changing wind directions with short fetch.


Forecasts for Ireland

TODAY ... Periods of rain becoming heavy, 20-40 mms potential for most but 30-60 mms locally, severe local flooding where ground saturated from previous rain. Moderate to heavy rain in ESE winds 25-45 mph will soon appear across central counties (in the east-west sense) and later into the north. Winds across the south will peak during the morning or mid-day from a SSE direction, reaching 40-70 mph and gusting to near hurricane force at times. There is potential for moderate structural and tree damage. Very exposed higher terrain could see gusts to near 100 mph. Around the southeast and east coasts and well inland, winds will rise to about SE 30-55 mph and will veer rapidly to SW 30-50 mph. Some squally showers or storms could develop along the windshift and the risk for local tornadic wind streaks will be monitored, especially valid around Limerick and Tipps north into the Athlone district and including Laois-Kilkenny.

Connacht will see a more gradual increase in wind speeds all morning to reach SSE 40-60 mph and then a gradual turn to SSW 40-60 mph with higher gusts possible. Ulster may be somewhat protected from the strongest winds and will see wind speeds of about 30-50 mph. There could be some brighter or even sunny intervals later in the day across the southwest and the storm will gradually subside to more of a partly cloudy, isolated showers scenario with winds SW 20-40 mph. Squally and at times heavy rain will continue over many other regions to about midnight or later. Highest temperatures will be 16-18 C for most, 18-20 C in parts of southwest and north Donegal (Malin Head could hit 21 C).

TONIGHT ... Further improvements are expected to clear spells, passing showers, winds SW 25-40 mph although 35-55 mph in the northwest, and lows 10-14 C. Rainfalls about 5-10 mms, although 10-20 mms Ulster which will now be getting the stronger part of the storm (although weakening as it goes, winds SSE 30-50 mph in east Ulster).

THURSDAY ... Cloudy with sunny intervals, breezy to windy (SW 25-45 mph), passing showers turning to squally thundershowers later and overnight, potential for 10-20 mms further rain especially south. Highs 18-22 C.

FRIDAY ... Cloudy, a bit cooler, fresh SW to W breezes, showers. Highs around 17-21 C.

WEEKEND OUTLOOK ... Variable cloud, isolated showers or more frequent showers in some western counties, near average temperatures (18-22 C). There could be some longer sunny intervals and warmer readings for eastern counties in a southwest wind flow.

FURTHER OUTLOOK ... Next week could see somewhat warmer temperatures again with some dry spells returning. Highs could reach 22-24 C. There may be extensive marine cloud in lighter winds and another rainfall situation mid-week if a frontal disturbance breaks through this weak ridge.


Forecasts for Britain

TODAY ... The severe storm will tend to stall to the southwest of most of Britain with peak gusts around 60 mph in Cornwall and parts of Wales. The wind direction will remain SE for most places and a line of squally showers or thunderstorms will try to push east through Wales and about Somerset-Dorset but may not make it too much further east before fragmenting. Despite that, a few severe storms could break out further northeast into the Midlands and Yorkshire. Highs about 22-25 C east of that front all the way up into Scotland, closer to 18-20 C where the front does manage to move through. Winds SE to S 30-50 mph for most, some higher gusts.

TONIGHT ... Variable cloud, remnant showers, blustery southerly winds veering more to southwest in regions closest to Irish Sea. Mild with lows around 14-17 C.

OUTLOOK ... The rest of the week could stay a little warmer than average with highs 22-24 C. Rainfalls will be heavy in parts of west and north again on Friday, moderate central and possibly continuing rather dry in the southeast although not totally so, as the storm track continues to run across northern Britain.


North American forecasts

Severe storms likely across west-central Canada with much cooler temperatures replacing the hot, humid air mass by evening in Manitoba, earlier for Saskatchewan, and for Alberta highs will only reach 15-18 C with hail showers at times. This colder air has only given B.C. a glancing blow and the coast will remain partly cloudy and very warm. Most of the western U.S. will remain warm except parts of Montana and Idaho. This front will extend further south late today and pull in some developing storms from the central plains states. Variable cloud and seasonable temperatures further east, generally speaking the intense heat wave is moderating and has ended for the time being in the northeast and Great Lakes regions.

MTC's LOCAL WEATHER (Tuesday) was sunny and very warm after some morning cloudiness, highs 27-30 C.

Updates on the storm as required, but check the discussion thread and observations reporting thread for all the latest details.

[M.T. Cranium]

Important: Please note legal disclaimer published once a month, can be seen at bottom of post 2565 dated 24 July 2012.

Thursday, 16 August, 2012
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TODAY ... Connacht will continue to see blustery SW winds 30-50 mph with passing squally showers about to move inland this morning, some of these with hail and thunder. Less active showers further south will move rapidly northeast and intensify somewhat in phase with the Connacht showers; meanwhile, some long dry spells and occasional sunny spells will develop as the winds turn more southerly again, backing to southeast 10-20 mph. Highs will range from 17 C in the northwest and Kerry to about 21 C east Leinster and Ulster.

TONIGHT ... Heavier showers with some embedded thunder will develop rapidly around sunset and will sweep northeast across most regions overnight; these will bring 15-30 mms rain and occasional wind gusts to about 35 mph (veering SE to SW). It will be very mild with lows only falling to about 17 C in Dublin and 15 C further west.

FRIDAY ... Variable cloud with further showers, another organized frontal band possibly giving 10-20 mms rain late in the day, but pleasant sunny intervals before that arrives with highs reaching 20-22 C.

SATURDAY ... Morning showers ending, sunny intervals, lows near 14 C and highs near 20 C.

SUNDAY ... Increasing cloud, showers or periods of rain developing, a bit cooler for most, lows near 12 C and highs near 18 C.

FURTHER OUTLOOK ... Some dry spells with near normal temperatures or slightly warmer, becoming more unsettled and cooler as the week unfolds.


Forecasts for Britain

TODAY ... Scattered morning showers more likely in Wales and western Scotland, afternoon thunderstorms in a few spots but some sunshine and highs near 23 C away from cooler west-facing coasts.

TONIGHT ... Showers or thunderstorms, heavy at times west, lows 14-18 C.

OUTLOOK ... Similar to Ireland in general, occasional showers, a little warmer than average to the weekend, a drying trend early next week. Typical highs will be 23-26 C south, to 18-21 C Scotland.


North American forecasts

The main feature is a slow-moving frontal system bringing heavy showers and thunderstorms to the Midwest and central-western Great Lakes. This will take another day on Friday to clear the eastern Great Lakes and Ohio valley which will be dry and warm today. Another area of heavy showers can be found over eastern Canada. Most of the south central and western states and adjacent western Canada are under hot, dry high pressure with heat wave conditions over all of the west now, highs well into the 30s.

MTC's LOCAL WEATHER (Wednesday) was sunny and hot, high near 31 C. Similar expected today and Friday.

[M.T. Cranium]

Important: Please note legal disclaimer published once a month, can be seen at bottom of post 2565 dated 24 July 2012.

Friday, 17 August, 2012
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Astronomy note: New moon occurs today at 4:56 p.m. IST.

TODAY ... Partly cloudy and warm with another round of heavy showers and embedded thunderstorms likely afternoon and evening hours, 10-20 mms rain, highs 18-22 C (warmest east). Winds occasionally SW 15-30 mph.

TONIGHT ... A few more showers or thunderstorms then clearing, mild, breezy, lows 12-15 C.

SATURDAY ... Yet another dry start leading to a showery or even stormy afternoon or evening, highs 18-21 C.

SUNDAY ... Partly cloudy, showers or a period of rain, lows near 12 C and highs near 19 C.

OUTLOOK ... Continued rather unsettled, highs in the 18-21 C range. A cooler interval seems likely in about a week.

Forecasts for Britain

Showers and thunderstorms likely each day from now to Monday, warm with southerly winds and highs in the range of 22-25 C south, 17-20 C north.

Forecasts for North America

Heavy showers and storms in eastern Great Lakes and Ohio valley, sunny and hot across the central and western regions (very hot in the western inter-mountain valleys, some places in southern B.C. near 40 C).

MTC's LOCAL WEATHER ... Thursday was sunny and hot, 32 C and Friday looks similar.

Sorry this is a bit sketchy today, I am about halfway into holiday mode and will be handing over the daily forecasting to the team in a day or two.

[M.T. Cranium]

Important: Please note legal disclaimer published once a month, can be seen at bottom of post 2565 dated 24 July 2012.

Saturday, 18 August, 2012
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TODAY ... Partly cloudy, longer sunny spells likely in parts of eastern counties, slight risk of showers mainly northwest this afternoon. Warm with highs around 21 C except 17-19 C near west, south coasts. Some coastal mist and offshore fog banks.

TONIGHT ... Partly cloudy with clear intervals, slight risk of a shower west, lows around 10 C.

SUNDAY ... Increasing cloud, showers and chance of a thunderstorm, 5-10 mms of rain on average, locally heavier, highs 18-20 C.

MONDAY ... Sunny intervals, back to a slight risk of a shower, lows 8-10 C and highs 18-20 C.

TUESDAY ... Increasing cloud, periods of rain developing, lows near 9 C and highs near 17 C.

WEDNESDAY ... Partly cloudy, passing showers, some heavy with hail and thunder, fresh WSW to WNW winds 20-40 mph, lows near 8 C and highs in the range of 15-18 C.

FURTHER OUTLOOK ... A more unsettled period with cooler temperatures appears likely with long-term models showing potential for rain next weekend.


Forecasts for Britain

In general, a similar pattern perhaps about a half-day behind, which means that some of the heavy showers from Friday are now moving through northern England today. TODAY will see passing showers, chance of a thunderstorm, highs 17-20 C north, 20-25 C south. This temperature range will continue through much of the week with a slight cooling trend after Wednesday which could be quite a stormy day in parts of central England.


Forecasts for North America

Northeast U.S. will see showers and thunderstorms. The southeast will experience frequent heavy showers and thunderstorms. Somewhat drier in the Great Lakes, Ohio valley, then a weak front with isolated showers further west around the Midwest ... the west remains under a dome of hot, dry air with near record high temperatures. After doing very little for over a week, tropical depression 7 decided to become a tropical storm in the southwest Gulf of Mexico. Meanwhile, Gordon took on a name from its origins as t.d. 8, so that's unusual. Gordon threatens the Azores with a minimal hurricane but a stronger tropical storm than Ireland saw last week (just kidding, it wasn't quite a named tropical storm). Winds could gust as high as 80 mph as this slowly approaches then passes through the Azores. In five days, Gordon is supposed to be dying out just west of Lisbon and still heading more east than northeast.

MTC's LOCAL WEATHER (Friday) was sunny and very hot, felt like 35 C to me, but I don't have an official thermometer.

[M.T. Cranium]

UPDATE _ Sunday, 19 August 2012 _ 0600h
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MTC on holiday for a week ... you may get some guest forecasters, if the weather gets active. This update of the previous forecast is based on the current guidance.

SUNDAY ... Increasing cloud, showers and chance of a thunderstorm, 5-10 mms of rain on average, locally heavier, highs 18-20 C. Looks like heavier rain will just miss most of the southeast, could catch east Wexford this morning; otherwise, outbreaks of light or moderate rain.

MONDAY ... Sunny intervals, back to a slight risk of a shower, lows 8-10 C and highs 18-20 C. Still looks to be the best day in the next 3-4.

TUESDAY ... Increasing cloud, periods of rain developing, lows near 9 C and highs near 17 C. Back to a familiar early summer pattern.

WEDNESDAY ... Partly cloudy, passing showers, some heavy with hail and thunder, fresh WSW to WNW winds 20-40 mph, lows near 8 C and highs in the range of 15-18 C. Higher pressure builds in later, could be fairly pleasant late in the week, and that ridge will be holding off remnants of Gordon which will move through the Azores on Monday, then slowly edge towards Portugal. Most guidance shows it weakening below tropical storm status by Friday and a weak remnant low could move inland near Lisbon around Friday. At that point, another low in the mid-Atlantic will edge towards Ireland and bring cool, unsettled weather for the weekend.

Due to my transition to holiday I won't update UK or NA forecasts except to say little change in general. It turned cloudy here with the sea breeze keeping the heat down somewhat at 24 C mid-day, while it was still 30-35 C a bit further inland.

Unless Gordon comes towards Ireland as a strong storm, it's likely that this will be my last post for a week, back on Monday 27th.

[pauldry]

Here is the weather for the week from Met Eireann.

http://www.met.ie/forecasts/