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

M.T. Cranium · 18-07-2010 06:16AM

Sunday, 18 July, 2010
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TODAY ... heavy morning showers across the southeast will fade out while some morning sunny breaks interrupt the cloudy conveyor belt from the southwest, but heavy rain may develop shortly after mid-day in the west arriving further east by late afternoon. Winds today will be SSW 15-25 mph and highs around 19-20 C with high humidity. Rainfalls of 10-25 mms can be expected.

TONIGHT ... cloudy and mild with further showers, some heavy, and slight chance of thunder, with 10-20 mms of rain in some areas, lows near 14 C.

MONDAY ... variable amounts of cloud with showers, and another period of heavier rain with some thunder by late in the day, foggy over hills, highs 18-20 C. Another 10-20 mms of rain on average, 30 mms in some western counties.

TUESDAY ... cloudy and humid with periods of rain, some thundery and heavy showers, 15-35 mms of rain, highs near 19 C.

WEDNESDAY ... morning showers, gradual clearing to follow, highs near 18 C.

THURSDAY to SATURDAY ... at present, indications point to a drier pattern setting in, with more sunshine than cloud, and warmer temperatures setting in after Thursday's high near 18 C, possibly 22-24 C in some places by Saturday.

The weather here has remained ideal with mostly sunny skies, low humidity, and comfortable daytime highs around 23 C. Hot and humid in eastern states and parts of Canada too, but very hot over the plains states on Saturday as desert air flowed out into Kansas, highs of 42 C there in some places -- this dry air quickly becomes very humid over the corn belt, dew points in Kansas ranged from 10 C in the west to 27 C in the east.

Well then, it looks like a few more days of this dismal heavy rain, then perhaps a break? But now we're fighting both recent trends and St Swithin.

M.T. Cranium · 18-07-2010 06:45PM

UPDATE _ Sunday, 6:45 p.m.
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Just a couple of notes about the rainfall potential later in the week. The charts are showing a heavy rainfall situation developing late Tuesday and lasting into parts of Wednesday, with a renewed surge of stormy potential (see some of the other threads for more details on this) on Thursday.

There are still fairly good indications for improvement beyond Thursday, fingers crossed on that.

M.T. Cranium · 19-07-2010 06:32AM

Monday, 19 July, 2010
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TODAY ... heavy thundery showers this morning in the southeast, otherwise just a few outbreaks of light rain or showers ... some brighter intervals with limited sunshine mid-day, then further heavy showers by afternoon, evening. Very humid with highs 18-20 C. Rainfalls quite variable, 5-10 mms at least, 15 to 35 mms locally (the north in general will see less).

TONIGHT ... foggy with showers or periods of rain, very mild, lows 14-16 C.

TUESDAY ... some brighter intervals moving across the country first part of the day, but heavy showers and thunderstorms may follow especially in the south and west. Highs 19-21 C. Rainfalls 10-30 mms.

WEDNESDAY ... further heavy showers, turning a bit cooler in northerly breezes, risk of heavy thunderstorms in the east. Highs 17-18 C. Rainfalls 10-30 mms.

THURSDAY ... cloudy, showery, although some clearing may develop in parts of Connacht in a moderate northerly flow. Highs 17-19 C.

FRIDAY ... gradual improvements although still the risk of a shower mainly in the east and southeast. Highs 18-20 C.

OUTLOOK ... warmer next weekend and beyond, possibly very warm at times with highs into the 20s.

Check out the other active threads on storm potential and watch for updates here too.

Sunday (18th) here was a mostly sunny, breezy day and a bit cooler than previous days, highs 20-21 C. A little further south, marine cloud kept it really cool in Seattle and most of western WA state. But a broiling heat wave has developed further south and inland, causing highs near 40 C in parts of Colorado, Kansas and Oklahoma. That very hot air is streaming east, picking up a lot of humidity from the maturing corn crops and the southerly flow off the Gulf of Mexico, and highs are regularly hitting 34-35 C on the east coast. Heavy storms are moving through Ontario tonight (local time).

M.T. Cranium · 19-07-2010 06:21PM

UPDATE _ Monday, 6:20 p.m.
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The latest guidance offers no relief from the potentially heavy rainfall events west to east on Tuesday and Wednesday. Looks as though Connacht will see the heaviest rain later tomorrow, and the southeast broadly defined will see it on Wednesday, with Tuesday night wettest in the Midlands as the system moves in a somewhat south of due east direction across Ireland.

There is potential here for some local rainfall totals of 30-50 mms and severe flash flooding to develop as a result. Also some of the thunderstorm activity could become intense, I doubt that there would be very much wind damage or hail potential, more of the torrential rain, intense lightning combination, but you can never rule out localized wind and hail damage with intense thunderstorm clusters.

It will be one to watch closely, so fasten your seat belts, turbulence ahead.

Kind of a cloudy, cool start here thanks to the marine layer holding tough, patches of blue sky playing hide and seek with the sun so far. About 16 C at 1020 local time.

M.T. Cranium · 20-07-2010 06:37AM

Tuesday, 20 July, 2010
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TODAY ... partly cloudy, warm and humid to start, with a few isolated morning showers, then outbreaks of heavy showers, some becoming thundery, moving inland from the west coast, while surface winds remain SE 10-20 mph. Some of these rain showers may produce torrential rainfall and intense lightning, with Mayo, Galway, Clare and Limerick more at risk, then later counties a bit further east. Highs today will range from about 18 C in the west to 22 C in the inland portions of Leinster. Rainfalls of 15-30 mms are possible in the west.

TONIGHT ... heavy, thundery showers becoming widespread, with hill fog developing, and 15-30 mms further rainfall, lows near 14 C.

WEDNESDAY ... the heaviest thundery rainfall will now be in the southeast and central counties, but the west and north will remain wet and turn cooler. Highs will be 14-17 C for most, possibly 18-19 C in the southeast. There is some chance of severe thunderstorms in Wexford, Carlow and Wicklow. Rainfalls will amount to 5-15 mms west and north, to 15-30 mms south and east.

THURSDAY ... partly cloudy with further showers, one or two of these thundery and heavy, but some places remaining dry. Winds northerly 10-20 mph, lows near 12 C and highs near 19 C.

FRIDAY ... sunny intervals, some coastal low cloud or mist, warmer, highs near 22 C inland.

SATURDAY ... partly cloudy with some risk of low cloud obscuring the sun near the coasts, but warm sunshine developing inland, highs 19-24 C.

SUNDAY ... there is potential for a very warm day but with all the moisture from the predicted rainfall, some forecasts are understandably mentioning a lot of low cloud ... I will take the optimistic route and call for some very warm sunshine to develop except close to the south and west coasts which may remain fogged in for a while. The highest temperatures will probably exceed 23 or 24 C and could reach 27 C if there's enough sunshine.

MONDAY will also be very warm with increasing cloud, highs 24-27 C.

TUESDAY to THURSDAY of next week are currently looking a bit cooler with scattered showers again. This may turn out to be a somewhat less widespread rainfall as the upper level flow is beginning to warm up.

Today (Monday 19th) was sunny by mid-day here, and about 22 C for an afternoon high. It remains very hot and humid across most of the U.S. and parts of southern Canada, but even hotter weather is likely by the weekend on the east coast.

Watch for updates and consult the ongoing threads for more details about today and tonight ... the system is currently just offshore around 15 W and heading in towards Galway from a direction of about 280 deg (in other words, it's moving just a bit south of due east). My thinking is that once this gets over land and encounters the warmer and more unstable air, it should develop rather rapidly this afternoon.

M.T. Cranium · 20-07-2010 05:41PM

UPDATE _ Tuesday, 5:40 p.m.
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The heavier showers are likely to move onshore this evening in western counties, and I am including Kerry and Cork in the alert for heavy rainfalls overnight. There are also some locally heavy thundery showers developing well ahead of the main batch and these will tend to drift north then northwest towards Ulster.

I still think the system has potential to drop heavy rainfall in most parts of Ireland overnight and on Wednesday, and then it will tend to break up during the morning on Thursday and hopefully this will be the start of a warmer, drier interval.

TheMilkyPirate · 20-07-2010 06:04PM

M.T. Cranium wrote: »

Tuesday, 20 July, 2010
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TODAY ... partly cloudy, warm and humid to start, with a few isolated morning showers, then outbreaks of heavy showers, some becoming thundery, moving inland from the west coast, while surface winds remain SE 10-20 mph. Some of these rain showers may produce torrential rainfall and intense lightning, with Mayo, Galway, Clare and Limerick more at risk, then later counties a bit further east. Highs today will range from about 18 C in the west to 22 C in the inland portions of Leinster. Rainfalls of 15-30 mms are possible in the west.

TONIGHT ... heavy, thundery showers becoming widespread, with hill fog developing, and 15-30 mms further rainfall, lows near 14 C.

WEDNESDAY ... the heaviest thundery rainfall will now be in the southeast and central counties, but the west and north will remain wet and turn cooler. Highs will be 14-17 C for most, possibly 18-19 C in the southeast. There is some chance of severe thunderstorms in Wexford, Carlow and Wicklow. Rainfalls will amount to 5-15 mms west and north, to 15-30 mms south and east.

THURSDAY ... partly cloudy with further showers, one or two of these thundery and heavy, but some places remaining dry. Winds northerly 10-20 mph, lows near 12 C and highs near 19 C.

FRIDAY ... sunny intervals, some coastal low cloud or mist, warmer, highs near 22 C inland.

SATURDAY ... partly cloudy with some risk of low cloud obscuring the sun near the coasts, but warm sunshine developing inland, highs 19-24 C.

SUNDAY ... there is potential for a very warm day but with all the moisture from the predicted rainfall, some forecasts are understandably mentioning a lot of low cloud ... I will take the optimistic route and call for some very warm sunshine to develop except close to the south and west coasts which may remain fogged in for a while. The highest temperatures will probably exceed 23 or 24 C and could reach 27 C if there's enough sunshine.

MONDAY will also be very warm with increasing cloud, highs 24-27 C.

TUESDAY to THURSDAY of next week are currently looking a bit cooler with scattered showers again. This may turn out to be a somewhat less widespread rainfall as the upper level flow is beginning to warm up.

Today (Monday 19th) was sunny by mid-day here, and about 22 C for an afternoon high. It remains very hot and humid across most of the U.S. and parts of southern Canada, but even hotter weather is likely by the weekend on the east coast.

Watch for updates and consult the ongoing threads for more details about today and tonight ... the system is currently just offshore around 15 W and heading in towards Galway from a direction of about 280 deg (in other words, it's moving just a bit south of due east). My thinking is that once this gets over land and encounters the warmer and more unstable air, it should develop rather rapidly this afternoon.

Woo!

M.T. Cranium · 21-07-2010 06:41AM

Wednesday, 21 July, 2010
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TODAY ... periods of rain this morning covering most of the north, central and western counties, dry but mostly cloudy for a while longer in the southeast ... heavier and thundery showers developing as the rain moves slowly further south and east, cool northerly winds covering most of the country, a bit warmer in the southeast, highs generally 14-16 C but locally 16-18 C in the southeast. Rainfalls today could reach 30-40 mms in some counties in an arc from about Dublin-Meath around to Cork, somewhat less further north and west, and more variable in the southeast where the rain will begin later but could be locally heavy. Risk of flash flooding in south central counties.

TONIGHT ... heavy, thundery rain continuing mostly south and east with a steady light rain on brisk northerly winds elsewhere. Lows 12-13 C, winds NNE 15-25 mph. Further rainfalls of 10-20 mms, possibly heavier in the east, with risk of flooding continuing and spreading more to eastern counties.

THURSDAY ... outbreaks of rain continuing but becoming more isolated to showers or local thunderstorms, sunny breaks developing, winds NNE backing to NW, 10-20 mph, lows near 12 C and highs near 18 C.

FRIDAY ... sunny intervals, warm and humid with highs near 22 C inland, but possibly lower around the west and south coast due to low cloud, fog and drizzle.

SATURDAY ... partly cloudy with some low cloud, fog and drizzle or light rain at times near west coast, rather warm and muggy, highs 18-23 C.

SUNDAY ... partly cloudy to sunny, very warm, muggy, highs 24-27 C inland and 18-22 C near the coasts.

NEXT WEEK ... now looking generally warm and dry but with some fog and low cloud at times in western and northern counties. Some highs in the mid to high 20s.

Meanwhile, today (Tues 20th) was partly cloudy to sunny here with a high of about 23 C. There have been scattered showers around the province this month but this location has had no rain since 29-30 June. Hot and humid across most of the central and eastern U.S., and aiming to get even hotter by the weekend in some eastern states.

Check the various forum threads as the day unfolds, I think it will be a case of some very heavy rains developing but in rather specific areas, with a few places holding on to dry conditions until well into the mid-day period.

M.T. Cranium · 21-07-2010 05:29PM

UPDATE _ Wed 5:30 p.m.
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Add the counties of Louth, Cavan, Monaghan, Armagh and Down to the list above for the heaviest activity this evening, with widespread thundery showers likely to continue to about midnight with further rainfalls of 10-20 mms and total rainfalls 20-40 mms possibly leading to some local flooding (in greater Dublin this would likely be flooded underpasses and areas near small streams that overflow quickly).

M.T. Cranium · 22-07-2010 06:16AM

Thursday, 22 July, 2010
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TODAY ... rather cloudy this morning with just a little more rain falling mostly in the lakeland counties, then some sunshine breaking through, allowing one or two showers to develop, locally heavy with thunder possible, but not likely to be very widespread ... and a steady N-NW breeze 10-20 mph somewhat gusty at times. Highs 16-18 C.

TONIGHT ... gradual clearing, fog patches developing, some low cloud near the west coast, lows 8 to 11 C.

FRIDAY ... partly cloudy with more widespread cloud or mist near the west coast, becoming mostly sunny further east and warmer again, highs near 20 or 21 C.

SATURDAY ... variable cloud, more of a low cloud or mist near the west coast at times, hazy sunshine further east, but some outbreaks of light rain or drizzle mostly west and north, warm and humid. Lows near 11 C and highs in the range 18-23 C (possibly warmer if long intervals of sunshine develop inland south).

SUNDAY ... sunny intervals, still some risk of low cloud or fog at least in the morning near the west coast, otherwise very warm and rather muggy with lows near 12 C and highs 23-26 C.

MONDAY ... partly cloudy with warm or even hot sunshine in places, isolated showers developing with risk of a thunderstorm, highs near 27 C.

The outlook for the rest of the week continues rather warm with some increase in shower probability on Tuesday, as a weak front drifts across the country then retreats, so that later in the week it may be one of the hotter periods of the summer with highs 26-29 C possible.

Here, we've had yet another dry and partly sunny day although it has clouded over this evening (Wed 21st here) and some showers may develop overnight. Tropical storm Bonnie is trying to form out of a complex low north of Haiti; if it does form, it would head for the southern Bahamas and the Florida Keys, move into the Gulf of Mexico and then possibly towards the oil discharge area by about Monday-Tuesday (as a tropical storm, not much indication of this becoming a hurricane).

If anyone's heading to NYC or other east coast cities, prepare for a strong heat wave, it has been around 32-34 C for days but may reach 38-40 C by the weekend, temperatures that have been common in Kansas and Oklahoma all week.

df1985 · 22-07-2010 04:26PM

im praying this comes good!

lucy2010 · 22-07-2010 04:34PM

http://www.wetterzentrale.de/pics/avnpanel1.html

is this worth getting excitied about ???? All those H's & red bits:D lol

M.T. Cranium · 23-07-2010 06:01AM

Friday, 23 July, 2010
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TODAY ... partly cloudy with much of the cloud being higher level letting some sunshine through, but with more widespread lower cloud or mist near the west coast, at times mostly sunny further east, somewhat warmer again with highs 18 to 21 C.

TONIGHT ... rather cloudy, warm and humid with drizzle or light rain mostly confined to west coast, lows 11-13 C (could be 9-10 C in some inland eastern rural locations due to longer intervals of clear skies).

SATURDAY ... variable cloud, more of a low cloud or mist near the west coast at times, hazy sunshine further east, but some outbreaks of light rain or drizzle mostly west and north, warm and humid. Highs in the range 18-23 C (possibly warmer if long intervals of sunshine develop inland south).

SUNDAY ... sunny intervals, still some risk of low cloud or fog at least in the morning near the west coast, otherwise very warm and rather muggy with lows near 12 C and highs 23-26 C.

MONDAY ... partly cloudy with warm or even hot sunshine in places, isolated showers developing with risk of a thunderstorm, lows 11-13 C, highs 24-27 C.

TUESDAY ... isolated showers, considerable cloud with some afternoon sunshine, a bit cooler in light NW winds, lows near 13 C and highs near 22 C.

WEDNESDAY ... partly cloudy, breezy, rather warm, lows near 11 C and highs near 23 C.

THURSDAY and FRIDAY ... from this distance, looking quite warm or even hot, with at least partly sunny skies, and highs potentially well into the 20s away from the cooler west coast due to onshore winds there. There may be a 29 or 30 C reading if the maps verify. This warm spell may reload and either return or continue through the weekend to follow.

Keep in mind that the ground is now quite wet and there will be a lot of evaporation in these warmer conditions, so any slight chance of a shower could be more potent than would often be the case given the proximity of strong high pressure. Also, the guidance could just turn out to be a bit optimistic in which case these very warm conditions may turn out a little more seasonable, but in any case, the pattern looks much improved over the past three weeks.

Meanwhile, Thursday (22nd) here was a mostly cloudy and breezy day, cooler than we've had most of the past week, high near 18 C, and a few sprinkles locally, nothing measurable ... further east, heavy showers and in one town in Saskatchewan, enough hail to resemble a late season snowstorm. From a frontal system further east, Milwaukee recorded as much as eight inches (200 mms) of rain in heavy thunderstorms, with tornadoes also reported nearby. This rainstorm is moving towards southern Ontario while severe heat is spreading across the northeastern U.S. with predictions of highs near 38 C for the next three days in Washington DC. :eek:

TheMilkyPirate · 23-07-2010 12:22PM

M.T. Cranium wrote: »

Friday, 23 July, 2010
Meanwhile, Thursday (22nd) here was a mostly cloudy and breezy day, cooler than we've had most of the past week, high near 18 C, and a few sprinkles locally, nothing measurable ... further east, heavy showers and in one town in Saskatchewan, enough hail to resemble a late season snowstorm. From a frontal system further east, Milwaukee recorded as much as eight inches (200 mms) of rain in heavy thunderstorms, with tornadoes also reported nearby. This rainstorm is moving towards southern Ontario while severe heat is spreading across the northeastern U.S. with predictions of highs near 38 C for the next three days in Washington DC. :eek:

Serious rain! In what sort of a timespan m.t?

M.T. Cranium · 23-07-2010 06:53PM

Most of that rain fell in 3-6 hours, from about 4 p.m. to 10 p.m. local time. Right now the hot, humid air mass has temps of 34-35 C and dew points of 24-26 C over much of Ohio, so there could be a repeat of these very heavy rainfalls later today in parts of Michigan, Ontario and New York state to the north of the frontal boundary. It may not be quite this dramatic but I'll report on the heaviest falls I can find in the morning (your time).

This is a Canadian radar site near London, Ontario ... right now it is relatively quiet but have a look at this later on and it may show some of the heavier rainfalls.

http://www.weatheroffice.gc.ca/radar/index_e.html?id=WSO

M.T. Cranium · 24-07-2010 07:09AM

Saturday, 24 July, 2010
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A "regime change" is setting in, with much warmer air flowing in from the southwest. The big question will be this: how much sunshine will manage to burn its way through extensive low level cloudiness that will accompany the warmer air in the lower levels? I discussed this yesterday, and on another thread Darkman2 takes a look at the question; he thinks it might make it to as high as 26 C at times -- I think there's some potential for it to get even higher than that by the end of the week. Some of the warmest air of this summer will be crossing the Atlantic from a source region that is racking up some record high temperatures this weekend (check the end of this post for more details on that). Forecasts follow ...

TODAY ... The morning hours will be rather dull and drizzly in places, then it should brighten to at least sunny breaks although the west and north coasts could stay cloudy or even foggy in places. Otherwise, with the brighter afternoon skies, expect warm highs of 20-23 C (17-18 C west, north coasts).

TONIGHT ... Partly cloudy with long clear intervals in some eastern counties, but the fog or low cloud possibly staying in place in some west coast locations. Lows therefore higher west, 11-13 C and lower east, 8-10 C.

SUNDAY ... Sunny intervals and quite warm, with the ever-present caution of some low cloud or mist near the west coast, highs into the 22-25 C range further east (17-19 C west coast).

MONDAY ... Sunny to start, clouding over during the day, possible showers by late in the day in Connacht, and quite warm for most, highs 23-27 C.

TUESDAY ... Cloudy with sunny intervals and turning a bit cooler, occasional showers more frequent in the north and probably heavier in the morning, highs 18-21 C.

WEDNESDAY ... Sunny intervals again, warmer, highs away from the west coast may return to 22-25 C.

THURSDAY-FRIDAY ... This is looking potentially very warm and sunny but there could be a lot of cloud in western counties, so that temperatures will tend to vary from 18-20 C west to about 25-27 C further east (assuming enough sunshine gets through the cloud). This will be the same hot air mass that I talk about below currently spreading across the eastern U.S.; the models show this crossing the Atlantic where it's very likely to pick up a shallow layer of stable cloud at about 1 to 3 thousand feet, but hopefully this will begin to break up over land.

So, while the weather was sunny and pleasantly warm here on Friday (23rd), it was very hot across the eastern U.S. except in New England where yesterday's heavy rains showed up as part of a warm front. Highs were 36-39 C in the Washington DC region. Even higher temperatures could be on tap for Saturday and Sunday, we shall see ... but this hot air is now being pushed along by strong westerly winds. It will cool off a bit next week in this region, but will stay above normal for the region.

Have a great weekend.

Redsunset · 24-07-2010 12:44PM

GFS UPDATE

DUE TO THE COMPLEXITY OF THE IMPLEMENTATION OF THE GLOBAL FORECAST SYSTEM AND ALL DOWNSTREAM DEPENDENCIES...THE EFFECTIVE DATE OF THE UPGRADE IS BEING RESCHEDULED FOR WEDNESDAY JULY 28. IF THE NWS DECLARES A CRITICAL WEATHER DAY ON OR AROUND JULY 28 THE IMPLEMENTATION MIGHT BE DELAYED. ANOTHER TIN WILL BE SENT IF THIS OCCURS.

EFFECTIVE JULY 28 2010...BEGINNING WITH THE 1200 COORDINATED UNIVERSAL TIME /UTC/ RUN...THE NATIONAL CENTERS FOR ENVIRONMENTAL PREDICTION /NCEP/ WILL UPGRADE THE GLOBAL FORECAST SYSTEM /GFS/. THE RESOLUTION OF THE GLOBAL FORECAST MODEL WILL BE INCREASED FROM T382 /35 KM/ TO T574 /27 KM/. THE HIGH RESOLUTION PORTION OF THE FORECAST WILL BE EXTENDED FROM 180 HRS TO 192 HRS. WITH THIS EXTENSION 3 HOURLY OUTPUT WILL BE MADE AVAILABLE OUT TO 192 HOURS.

THIS WILL RESULT IN SIGNIFICANT CHANGES IN THE DEFINITION OF PARAMETERS IN THE 192 HOUR PRESSURE GRIB /PGRB/ AND FLUX FILES. THERE WILL ALSO BE SIGNIFICANT CHANGES IN MODEL PHYSICS ASSOCIATED WITH THIS CHANGE. IN ADDITION MODIFICATIONS WILL BE MADE TO THE CONTENTS OF THE GLOBAL DATA ASSIMILATION SYSTEM /GDAS/ AND GFS PGRB FILES.

CHANGES IN MODEL PHYSICS INCLUDE:
RADIATION AND CLOUD OVERLAP
GRAVITY WAVE DRAG
HURRICANE RELOCATION
NEW PLANETARY BOUNDARY LAYER SCHEME
NEW MASS FLUX SHALLOW CONVECTION
UPDATED DEEP CONVECTION SCHEME
POSITIVE DEFINITE TRACER TRANSPORT SCHEME
THE NEW PARAMETER FOR THE GFS FORECAST PRESSURE GRIB FILE IS:
MAX WIND GUST
SEVERAL PARAMETERS ARE BEING DELETED FROM THE GDAS ANALYSIS PRESSURE GRIB FILES BECAUSE THEY ARE NOT VALID FOR THE ANALYSIS DATASET AND HAVE NEVER PROVIDED PERTINENT INFORMATION. THESE INCLUDE:
4 PRECIPITATION TYPES
CONVECTIVE PRECIPITATION RATE
LAND SEA MASK
LATENT HEAT FLUX
SENSIBLE HEAT FLUX
PRECIPITATION RATE
2M RH
2M SPECIFIC HUMIDITY
2M TEMPERATURE
BOUNDARY LAYER CLOUD COVER
LOW CLOUD COVER
CONVECTIVE CLOUD COVER
SKIN TEMPERATURE
SURFACE UPWARD LONG WAVE FLUX
SURFACE UPWARD SHORT WAVE FLUX HELICITY
THESE PARAMETERS ARE BEING DELETED FROM THE GLOBAL FORECAST MODEL SIMULATED GOES GRIB FILE BECAUSE THEY WERE INCLUDED IN ERROR. THESE FIELDS ARE AVAILABLE IN THE PGRB FILES:
MEAN SEA LEVEL PRESSURE
WAVE-5 GEOPOTENTIAL HEIGHT
ALL ACCUMULATED OR AVERAGED VALUES IN THE 192 HOUR PGRB AND FLUX FILES WILL NOW BE OVER A 6 HOUR PERIOD INSTEAD OF 12 HOURS. THE FORMAT AND CONTENT OF THE 3 HOURLY FILES FROM 180 TO 192 HOURS WILL BE THE SAME AS THE FILES FROM 0 TO 180. FOR THE FLUX FILE...THIS INCLUDES THE MAJORITY OF THE PARAMETERS IN THE FILE. PARAMETERS CHANGING IN THE PGRB FILE ARE:
2 M ABOVE GROUND MAX. TEMPERATURE
2 M ABOVE GROUND MIN. TEMPERATURE
SURFACE ALBEDO
SURFACE CLEAR SKY UV-B DOWNWARD SOLAR FLUX
SURFACE CATEGORICAL FREEZING RAIN
SURFACE CATEGORICAL ICE PELLETS
SURFACE CONVECTIVE PRECIPITATION RATE
SURFACE CATEGORICAL RAIN
SURFACE CATEGORICAL SNOW
ATMOSPHERIC COLUMN CLOUD WORK FUNCTION
SURFACE DOWNWARD LONG WAVE FLUX
SURFACE DOWNWARD SHORT WAVE FLUX
SURFACE UV-B DOWNWARD SOLAR FLUX
SURFACE GROUND HEAT FLUX
SURFACE LATENT HEAT FLUX
SURFACE PRECIPITATION RATE
LOW CLOUD BASE PRESSURE
LOW CLOUD TOP PRESSURE
MID-CLOUD BASE PRESSURE
MID-CLOUD TOP PRESSURE
HIGH CLOUD BASE PRESSURE
HIGH CLOUD TOP PRESSURE
SURFACE SENSIBLE HEAT FLUX
ATMOSPHERIC COLUMN TOTAL CLOUD COVER
BOUNDARY CLOUD LAYER TOTAL CLOUD COVER
LOW CLOUD COVER
MID-CLOUD COVER
HIGH CLOUD COVER
LOW CLOUD TOP TEMPERATURE
MID-CLOUD TOP TEMPERATURE
HIGH CLOUD TOP TEMPERATURE
SURFACE ZONAL GRAVITY WAVE STRESS
SURFACE ZONAL MOMENTUM FLUX
SURFACE UPWARD LONG WAVE FLUX
TOP OF ATMOSPHERE UPWARD LONG WAVE FLUX
SURFACE UPWARD SHORT WAVE FLUX
TOP OF ATMOSPHERE UPWARD SHORT WAVE FLUX
SURFACE MERIDIONAL GRAVITY WAVE STRESS
SURFACE MERIDIONAL MOMENTUM FLUX
SURFACE CONVECTIVE PRECIPITATION
SURFACE TOTAL PRECIPITATION
SURFACE LARGE SCALE PRECIPITATION
NOTE THAT FOR THE 192 HR PGRB PRODUCTS AVAILABLE ON NOAAPORT AND IN AWIPS... THE ACCUMULATIONS AND AVERAGES WILL REMAIN OVER THE PREVIOUS 12 HOUR PERIOD UNTIL AWIPS IS MODIFIED TO ACCOMMODATE THIS CHANGE.

ONE ADDITIONAL CHANGE TO NOTE IS THAT THE FILE PGRBF192.GRIB2 ON THE NCEP FTP SERVER WILL CHANGE FROM CONTAINING MODEL OUTPUT ON A 2.5 DEGREE GRID TO CONTAINING MODEL OUTPUT ON A 1 DEGREE GRID. THE 2.5 DEGREE OUTPUT WILL BE PROVIDED IN A NEW FILE WITH THE NAME PGRBF192.2P5DEG.GRIB2.

THE FORMAT OF THE HALF AND ONE DEGREE PRESSURE GRIB FILES WILL REMAIN THE SAME EXCEPT FOR THE CHANGES IN VARIABLES LISTED ABOVE. THE SIZE OF THESE FILES WILL NOT CHANGE SIGNIFICANTLY. WITH THE INCREASE IN MODEL RESOLUTION...THE SIZE OF THE SIGMA COEFFICIENT FILES AND THE SURFACE FLUX FILES WILL INCREASE SIGNIFICANTLY.

DATA DELIVERY TIMING OF THE GFS WILL NOT BE IMPACTED BY THIS IMPLEMENTATION.

maquiladora · 24-07-2010 02:27PM

redsunset wrote: »

GFS UPDATE

EFFECTIVE JULY 28 2010...BEGINNING WITH THE 1200 COORDINATED UNIVERSAL TIME /UTC/ RUN...THE NATIONAL CENTERS FOR ENVIRONMENTAL PREDICTION /NCEP/ WILL UPGRADE THE GLOBAL FORECAST SYSTEM /GFS/. THE RESOLUTION OF THE GLOBAL FORECAST MODEL WILL BE INCREASED FROM T382 /35 KM/ TO T574 /27 KM/. THE HIGH RESOLUTION PORTION OF THE FORECAST WILL BE EXTENDED FROM 180 HRS TO 192 HRS. WITH THIS EXTENSION 3 HOURLY OUTPUT WILL BE MADE AVAILABLE OUT TO 192 HOURS.

T574? Aw man, so now we are going to get teased with FI snowfests 23 days in advance?

M.T. Cranium · 24-07-2010 07:26PM

UPDATE _ Saturday, 7:25 p.m.
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I notice that the 12z model runs are starting to back off the warming trend at least around Thursday-Friday. We'll have to see if this continues to the morning runs or not.

As to the GFS going to 574h, seeing as how most people call 192-384 hours "Fantasy Island" I am not sure what we'll be calling the 400s and 500s, maybe Planet X.

By the way, Chicago under flood emergency (which means that canals have overflowed, etc) after they got the eight inch rain special last night. Meanwhile, highest temp so far at DCA is 38 C, time for this to reach 39 or 40 C, way too hot for man and beast.

pauldry · 25-07-2010 01:59AM

Think July is 18 to 23c til end with drizzle till end in NW at times n sum sun.

Think start of Aug mite see a really hot 2 days like Monday 26th July which mite get near 25c

But rest of week will see 20c at best

IMO

If you say, MT, that hotter weather is promised I hope your right coz my shoulders n feet want it.

M.T. Cranium · 25-07-2010 05:42AM

There are wheels within wheels in this forecast situation, first of all there's the very open question of how warm it could get if the warm (aloft) air masses come streaming in, then during the past day we had a real flip-flop on model runs backing off from that warm air streaming in -- and now almost predictably at 0530 I am finding the model run back to the warm scenario again. Bwa-ha-ha etc. Pauldry, I think we'll just go with a wide range of possible temperatures and try to give some idea of the more likely days for the warmer outcomes. But this sort of scenario is by definition prone to large uncertainties or larger than usual.

Forecast around 0640 if I get some confirmation from a second model run now coming in.

M.T. Cranium · 25-07-2010 06:14AM

Sunday, 25 July, 2010
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For a while, it seemed that the computer models were backing off the warming trend we were discussing at this time yesterday, but now I'm finding them back onto that bandwagon -- there may be more reversals to come, because the situation upstream (over the eastern U.S.) is rather volatile and some features are backing up to the west over the next three or four days. This adds difficulty to the computer generated number crunching and so I should stress that these warm outcomes are subject to further revisions.

TODAY ... a reasonably warm and dry day, but with considerable cloud in western counties and possibly further east at times too, with patchy drizzle before the sun begins to break through. Highs likely to be 17-20 C west and 22-24 C east. Not too windy but at times a W-NW breeze of about 15 mph.
Also rather muggy especially under the low cloud in the west.

TONIGHT ... cloudy intervals, mild, some drizzle or low cloud at times near the Atlantic, lows 11-13 C.

MONDAY ... becoming sunny and quite warm away from the west coast, where low cloud may persist. Highs will therefore vary from near 20 C west to near 25 C east. Possible showers or thundershowers late in the day in Connacht.

TUESDAY ... Variable cloud, still some decent sunny intervals, but widely scattered showers and possibly a brief thundershower, highs near 22 C.

WEDNESDAY ... Fair, warming up slightly in the east, remaining near 21 C in the west but 24-25 C east.

THURSDAY-FRIDAY ... Partly cloudy and warm, some risk of showers but many places dry, highs 24-27 C (and potentially higher in a few places), although it may stay closer to 21 C near the west coast.

The further outlook calls for continued warm and dry conditions much of the time for another week or longer as a strong Azores type high begins to swell and move ever closer to Ireland. (confidence moderate rather than high on this) ... keep those fingers and toes crossed, that's really all I can say at this point, but the model runs do show a lot of warm air over the region for most of the period to about 8 August.

See previous posts for some details on weather over here on Saturday -- it was sunny and warm on the west coast, stormy around Chicago and very hot on the east coast (except in Boston which stayed fairly temperate). Even at midnight (Eastern time) it was 32 C at Washington DC -- after a high of 38 C. :eek:

ch750536 · 25-07-2010 01:13PM

Interesting forecast. You seem to be out on your own a little there MT. You did say several times 'in the west...' so we shall see. Personally it feels like it's going to continue with cool grey muck for me.

Current conditions - in low cloud, damp, 16c. Neg. wind.

M.T. Cranium · 26-07-2010 06:55AM

Monday, 26 July, 2010
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The Moon is at full phase today, in fact it was aligned at 0238 summer time, but if you can see it tonight you won't see any obvious reduction in the fully lit lunar disk.

TODAY ... Extensive low-level cloud early in the day will begin to break up to warm partly cloudy or even sunny conditions in the east and south, but while it may brighten somewhat in the west and north, frontal clouds will then arrive mid-day followed by one or two showers (earlier drizzle there may keep things damp for part of the morning). Highs will therefore tend to vary considerably from a range of 17-19 C west and north to 23-25 C east and south. Anywhere that manages to get a long sunny interval mid-day could even get a bit warmer, but then sea breezes on the south coast could also set in and bring readings down a few degrees, so things are complicated. In general, though, a warm and rather muggy day for most.

TONIGHT ... Cloudy with a few showers, heavier in the west and north, but eventually reaching most other locations. Only 2-5 mms likely, and a slight chance of thunder (not heavy). Lows will be 12-14 C.

TUESDAY ... Gradually brightening from the west as the showers drift further southeast and also lose intensity. Breezy from the west with gusts to 30 mph at times, and fresher than today, with highs 20-22 C.

WEDNESDAY ... While the persistent low cloud problem may return to plague the west coast, otherwise this may be a partly cloudy to sunny day with just the outside chance of a brief shower, still rather breezy from a west backing to southwest direction. After morning lows near 10 C, expect a high of about 23 C in the east and south (18-19 C west, 20-21 C north this time).

THURSDAY ... This could be a very warm day where low cloud parts, but the set-up is similar to yesterday, so that the south coast may be the best place to look for sunshine. Highs are likely to return to the mid-20s away from the west coast which will be about 20-21 C. Risk of showers increasing in Connacht and Donegal by late afternoon and evening.

FRIDAY ... Unless we get yet another model flip-flop before then, likely to become cloudy with sunny periods, widespread showers and chance of a thundershower, somewhat fresher and cooler with lows 12-15 C, and highs 21-23 C, westerly breezes at 15-30 mph.

The following weekend is now looking rather unsettled at first with a gradual trend to drier weather in a moderate WNW flow that remains near normal in temperatures (19-21 C highs). The long-range outlook seems to be drifting towards a consensus of this type of weather prevailing as strong Azores high pressure tends to remain a bit west of Ireland and shows some retrograde (east to west) drift at times. In that sort of pattern, the weather tends to be variable and not particularly wet although showery from time to time.

Looking at the North American weather on Sunday (25th) there was a rather abrupt end to the strong heat wave in eastern states with some gusty thunderstorms, but not before temperatures once again reached the 36-37 C range in places and 40 C or higher in Virginia. It will only cool off slightly to around 30-32 C in those states. Meanwhile, we are enjoying one perfect day after another, the high on Sunday was about 26 C, and humidity remains quite low.

lucy2010 · 26-07-2010 03:35PM

http://www.nratraffic.ie/weather/default.asp?RegionId=0

Bang on the button MT - Kells 28.5 c . trogs weather station right on the beach is recording 26.5c at present; just flew over to post office there 28.5c in the car .... Absolute scorcher..

pauldry · 26-07-2010 04:46PM

think kells is "generous" lucy.

Though your car might be accurate!

met eireann are not getting anything over 24 at their stations.

though we know how FU they are. Their radar doesnt even work.

Only jokin Met Eireann!:)

M.T. Cranium · 27-07-2010 06:56AM

Tuesday, 27 July, 2010
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TODAY ... skies should gradually brighten from the west as the patchy light rain and drizzle moves further southeastward, and the cloud begins to break to partly cloudy skies. Because this air mass is somewhat less humid, it may not fog up as rapidly on the west coast but some outer headlands could become misty. Highs today will be more uniform in the range of 20-22 C. Further rainfalls of only 1-2 mms likely, and winds freshening to WSW 15-30 mph. There could be one or two isolated showers later in Donegal and nearby counties.

TONIGHT ... variable cloudiness and a slight chance of a shower, but also some longer clear spells, fog or mist returning at times to the west coast, lows generally near 10 C.

WEDNESDAY ... partly cloudy with longer sunny intervals in the south and east, breezy with slight chance of showers mostly over the north, and a trend towards low cloud and mist returning to some western counties by afternoon. Highs near 22 C east, 18 C west.

THURSDAY ... turning very warm and muggy again with a low of only 15 C followed by highs in the range of 20-25 C west to east, with the usual regional variations of low cloud and mist in the west and far north, sunny breaks more likely east and south. There may also be some brief showers well inland.

FRIDAY ... variable cloud, still rather warm, showers and chance of a thunderstorm developing, lows near 15 C and highs near 23 C, winds freshening to WSW 15-30 mph. We'll have to keep an eye on potential for heavy thunderstorms in this set-up.

WEEKEND OUTLOOK ... gradually becoming more settled again in a dry, reasonably warm westerly flow, the west coast may not be all that foggy as the source of the flow is a bit further north, and yet it's not a particularly cool flow so that east and south could warm up to about 22 C.

All in all, probably about as warm as it ever gets in a maritime-origin flow, but not the sort of heat that can develop in a southeast flow from the near continent. The air mass by Thursday will be essentially the same one that was baking the eastern U.S. on the weekend, but after three days over the Atlantic in regions where seas are about 20-22 C most of the way, the lower levels become very stable and filled with low level cloud and fog as the air approaches the west coast. However, it won't take too long to dry out a bit and let some sunshine through.

Meanwhile, little change in the North American weather pattern, the east has cooled slightly (but still above normal) and here on the west coast Monday was sunny and very warm, it was about 27 C locally and 36 C further inland (a very dry heat here). Severe thunderstorms are raging tonight in Manitoba and North Dakota, moving into Minnesota. This front will be on the east coast by Thursday.

I hope your day turns out pleasant even if the first hour or two may be gloomy.

Speak Now · 27-07-2010 08:46AM

pauldry wrote: »

think kells is "generous" lucy.

Though your car might be accurate!

met eireann are not getting anything over 24 at their stations.

though we know how FU they are. Their radar doesnt even work.

Only jokin Met Eireann!:)

Despite reports of 27/28 from east coast the highest met eireann station yesterday was Oak Park with 24.2c.

lucy2010 · 27-07-2010 11:12AM

Jerry Seinfeld wrote: »

Despite reports of 27/28 from east coast the highest met eireann station yesterday was Oak Park with 24.2c.

You know the heat when you get off the plane in Lanzarote... Thats what it was like lol
Ill kill the kids for messing with the buttons in the car again lol

M.T. Cranium · 28-07-2010 06:53AM

Wednesday, 28 July, 2010
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TODAY ... A weak warm front will continue to bring some light rain or drizzle reaching eastern counties soon then dissipating by mid-morning, otherwise, the day should proceed mainly dry with variable cloud mostly of a middle to high level variety, with some sunny intervals. The west coast will see reduced visibility in mist then fog later as humidity levels rise, but otherwise it should be a bright, fine day mostly with good visibility. Any rainfall will amount to perhaps 1 mm locally. Winds will freshen again mid-day to WSW at 15-30 mph, tending to back southerly later. Highs will range from 19 C west to 22 C east (but it may take a while to get past 17 C this morning).

TONIGHT ... variable cloud and rather warm, muggy with local mist or fog in western counties, turning to drizzle at times there. Lows 13-15 C.

THURSDAY ... the warm wedge arrives, see the "late July heat wave" thread for more details on the set-up here, the forecast is complicated ... western counties will be mostly overcast with dense fog over some coastal waters and a mist inland to a distance of perhaps 30-60 kms. Even so, this could burn off late in the day to warm sunshine in places. Highs in the west are likely to edge up towards 20 C and perhaps 22-24 C in Kerry. Further east, while it may be cloudy at times, some sunshine will break through and it will feel oppressively warm and muggy, with highs of 24-27 C. Winds will be rather light southerly in most places.

THURSDAY NIGHT ... this could be one of the warmer nights of the summer with overnight lows falling only to 17-19 C, and the west coast may remain in dense fog while other regions have a light mist or partly cloudy skies. Rain will arrive in Donegal and spread to some other nearby counties after midnight.

FRIDAY ... rather warm still, and humid, but with a front arriving, some risk of heavy showers and even one or two thunderstorms (as I said, this will have to be watched closely as the details are clarified) ... highs of about 22-24 C although the northwest may stay near 20 C. Rather breezy at times with potential for strong wind gusts near thunderstorms.

SATURDAY and SUNDAY ... a fairly reasonable weekend although perhaps more cloud than sun for most, not much rain likely in a few widely separated passing showers, although an interval of light rain possible Sunday morning in the southwest. Highs each day 20-22 C and comfortable at night (11-13 C) with lower humidity than the next few days.

OUTLOOK ... rather cloudy and warm at times early in the week, likely turning a bit cooler mid to late week, at this point, not looking especially wet but a few showers at times.

Today here (meaning Tues 27th) we had our hottest day of the current long warm and dry spell, it was near 30 C inland and 25 C downtown near the sea under scorching blue skies. It's interesting that when we get a subtropical flow here the air masses tend to dry out and subside, becoming clear away from the coastal fog belt but that remains on the west side of Vancouver Island and not further inland around here in summer, sometimes in late autumn the coastal fog sets up on the inlets too and the city has local fog banks so that we get days with almost no visibility one place and clear sunshine a few city blocks away. Anyway, the rest of North America on Tuesday was fairly warm with the severe storms moving across Michigan and Wisconsin. The east coast has been sunny and very warm but not brutally hot with highs of about 31 C.

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

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