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Posted
  • Location: Skirlaugh, East Yorkshire
  • Location: Skirlaugh, East Yorkshire

Agree there- the cold upper air gets mixed out as the easterly establishes over southern areas, so I can see cloud cover being extensive and precipitation minimal over East Anglia and the SE if that scenario materialises- the GFS temperature projections also support this. Scotland and N England would remain sunny.

Re. GFS the Wetterzentrale 2m temperature outputs that I can see, both on here and on WZ itself, don't match up with what Eugene is showing:

http://www.wetterzentrale.de/pics/Rtavn725.png

The chart Eugene has posted is the dewpoint chart. :)

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Posted
  • Location: Bishopbriggs, near Glasgow
  • Weather Preferences: Cold snowy winters, warm dry summers
  • Location: Bishopbriggs, near Glasgow

Looks like this winter has introduced a new GFS default chart, the intense anticyclone centred over Denmark in far FI. Will need to get it about 500 miles further north for next winter!

SS2

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UKMO 12Z around T+60 hrs also brings in some cold uppers, looks like it will produce some very low dewpoints and bonechilling nights, just incredible how many >-15C's central scotland is recording lately, more >-7C's should be recorded in england and wales early next week before the cloudier easterly air moves into the midlands, south and eastern areas.

http://www.meteociel.fr/ukmo/run/UN60-7.GIF?04-17

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Posted
  • Location: Heswall, Wirral
  • Weather Preferences: Summer: warm, humid, thundery. Winter: mild, stormy, some snow.
  • Location: Heswall, Wirral

Looks to me like there's a glitch on that chart- there's no way we'll have 06-12Z maxima that low!

I have a quite strong amount of evidence which suggests that GFS occassionally wildly under or overpredicts temperatures at the 2m temperature level.

I will present the graphical and recorded findings come Spring (solar), however just as starting point, on the 18th February (valid for the 26th February) the GFS predicted -10 or -11C as a minimum come the day itself the minimum came through as +1 and +2C widespread around England and Wales.

More dubious predictions today, and to be honest I'm making the effort to collect data to back this up so I don't anyone suggesting "you always say this with nothng to back it up" I would not say it if I didn't see it.

Meanwhile the reality of the pattern is that we are continuing cold, although the NAO/AO forecasts suggest something milder and more unsettled (as per Meto 6-15 day outlook)

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Posted
  • Location: Lincoln, Lincolnshire
  • Weather Preferences: Sunshine, convective precipitation, snow, thunderstorms, "episodic" months.
  • Location: Lincoln, Lincolnshire

I think you are right Stephen, and I've noticed quite a number of projections of unfeasibly low minima during this winter from the GFS- they tend to occur under projections for snow cover and an Arctic regime, only to moderate considerably within T+48 to T+72.

Conversely minima are often overpredicted for East Anglia especially during cold spells where it's as if the GFS "thinks" Norwich is in the middle of the North Sea!

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Posted
  • Location: Sheffield South Yorkshire 160M Powering the Sheffield Shield
  • Weather Preferences: Any Extreme
  • Location: Sheffield South Yorkshire 160M Powering the Sheffield Shield

Interesting GFS only needs the High slightly further north to get some really cold air drawn in. As it it's looking like very cold nights too come up with sharp frosts around and rather cold by night. Cloud cover will be decider and that will depend on where the high ends up. Again strong signs of another below average month coming up.

Looking fairly dry though folks.

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Posted
  • Location: Weston Super Mare , North Somerset
  • Location: Weston Super Mare , North Somerset

There is obvious some mistakes in the GFS 12z .. Some charts would be extreme in January such as dew points .... It's not worth even discussing the possibility of it because it is zero .

There is a chance of some Snow showers early next week currently in the SE and Midlands. most models have been hinting at this , but nothing major .

Anybody that is taking some of the charts showing up seriously needs to learn more about the weather .

Just my thoughts don't shoot me .

Chris .

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Posted
  • Location: portsmouth uk
  • Weather Preferences: extremes
  • Location: portsmouth uk

well ive just looked at the jma gem gefs gfs gem and ukmo and all have -8 uppers coming and going as expected when the high pressure wobbles about most of the cold is for southern and southeastern areas.

with the -12s coming very close indeed in respect of what falls out of the sky nothing much by the looks of things either cloudy or dry and frosty looks most likely.

but its incredible how much this cooler/colder air is hanging on.:)

Edited by badboy657
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Posted
  • Location: Weston Super Mare , North Somerset
  • Location: Weston Super Mare , North Somerset

http://www.wetterzen...s/Rtavn9610.png - WTF surely an error those dewpoints in north wales especially are phenomenal in March, easily freeze still water those kind of dewpoints would.

It isn't showing like that on any of the Operational charts on any of the other Websites. Is that an Ensemble member ??

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Posted
  • Location: Caterham-on-the-hill, Surrey, 190m asl (home), Heathrow (work)
  • Location: Caterham-on-the-hill, Surrey, 190m asl (home), Heathrow (work)

Dew point chart, shows the very dry Saharan air. For example, this evening 1800UTC dew point at Tamanrasset in southern Algeria was -8c but the air temp was 27c which is about 10% humidity.

Seems to be some shock at the low dew points shown by GFS on here, though I don't think it is that unusual given the set-up and time of year. The low DPs shown over parts of UK early next week just show how dry the airmass will be, a combination of dry continental air advecting from the east and also dry air subsiding from aloft under the subsidence of high pressure. Negligible precip. showing as a result. Air temps generally around 5C progged across E & W by early afternoon Monday, despite some DPs dropping as low as -10C.

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Posted
  • Location: Eastbourne and Larnaca,Cyprus .
  • Location: Eastbourne and Larnaca,Cyprus .

Looks like a return to winter for mainland Europe with some very cold temperatures, we once again find the high unable to centre far enough north to deliver some of the coldest air into the UK with the main cold shot going into Germany and France, this has happened so many times in the recent winter.

The ECM this evening in FI looks a bit lost with a slack flow covering Europe and messy synoptics, a little interest for cold lovers in that the hint of high pressure toppling towards Scandi with a small chance this could let some colder air in from the ne.

Earlier developments in the Med look uncertain regarding low pressure development, how far north this goes as this could strengthen the flow across southern areas of the UK, interestingly some models still keep a colder pool to the east after the initial cold shot advecting westwards just skimming southern areas.

Edited by nick sussex
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Posted
  • Location: Crowle and Cleethorpes, Lincolnshire
  • Weather Preferences: Snow
  • Location: Crowle and Cleethorpes, Lincolnshire

Evening all, just taken a look at the GFS 12z, looks like an attempt at a northerly around 240-276, sure long way to go yet, but a below-average March looks almost certain.

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Posted
  • Location: Heswall, Wirral
  • Weather Preferences: Summer: warm, humid, thundery. Winter: mild, stormy, some snow.
  • Location: Heswall, Wirral

I dont think the GFS had underplayed the dewpoint, I think it's very possible dewpoint could get that low, because at this time of year the chances of inversions are subsiding although not gone this means that without any moisture trapped under the high pressure layer thing can get very dry.

I recall Feb or March 2003, high pressure settled ovr Scotland and brought some record or near record low humidity? There was as I remember heathland fires and snow falling at 10C because the air was so dry.

As for the temperatures, well I think perhaps the GFS is putting extremely low temperature in to account for the low dewpoints, I can understand that and can't moan, but in reality such set ups in March would give widely 0C to -2C with no hoar frost.

Interestingly maybe it's start to look a little like 2003, although inverted?

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Posted
  • Location: Ware, Herts
  • Location: Ware, Herts

If this set up with heights to our north continues, how long will it be before any easterly flow becomes exceptionally warm? Surely by around May the continent will be getting a lot warmer; if our present set up occurred in July it would be scorching wouldn't it?

As for the general outlook at present, I'd also back March at being below average. As long as we keep cold, clear nights it's going to prevent the CET getting too much above 5c.

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Posted
  • Location: Windermere 120m asl
  • Location: Windermere 120m asl

All models in agreement of a sustained settled spell courtesy of high pressure. Heights look very robust by the end of the week and gradually moving south during early next week which will allow for some cloudier conditions to move into northern parts of Scotland.

This high could stick around for a long time, expect subtle changes in where the models position the high in the coming days.

Longer term signals favour a westerly regime by mid month but there is every chance we see some shortwave developments to the north west with potential for a potent northerly. As March wears on the best set up for cold and snow becomes a northerly, think easter 2008, the arctic seas are at there coldest in early March and only very slowly warms up during the Spring, meaning a deep seated northerly will have little modification.

Edited by damianslaw
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Posted
  • Location: Liverpool
  • Location: Liverpool

Hi,

With this high pressure continuing in situ for a number of days is it possible we could see a snowy breakdown (i.e. a transitional snow event) if the Atlantic breaks through? Can the Atlantic pushing in against the HP result in a battleground type snow event I am thinking along the lines of March 2006 was that caused by LPs pushing against a HP in situ? Also is the trend to take the easterlies and hence the HP cells further south (therefore reducing the chance of precipitation over the British Isles) this winter a symptom of the jetstream being so far south?

Luke

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Posted
  • Location: Lincoln, Lincolnshire
  • Weather Preferences: Sunshine, convective precipitation, snow, thunderstorms, "episodic" months.
  • Location: Lincoln, Lincolnshire

I think Atlantic systems pushing against the current high pressure would be unlikely to give a significant snow event. The 12th March 2006 event resulted from a battle between Atlantic and continental air, the continent having just been cooled by a northerly outbreak. I think the Arctic air embedded within our high will end up too heavily modified.

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Posted
  • Location: Weston Super Mare , North Somerset
  • Location: Weston Super Mare , North Somerset

I Thought there would be at least 1 comment on the 00z , It gives lots of opportunity for Snow events in the SE and bitter NE winds from Mid next week with the High Moving North and -10 Uppers. Great run IMO

Edited by snowmadchrisuk
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Posted
  • Location: portsmouth uk
  • Weather Preferences: extremes
  • Location: portsmouth uk

I Thought there would be at least 1 comment on the 00z , It gives lots of opportunity for Snow events in the SE and bitter NE winds from Mid next week with the High Moving North and -10 Uppers. Great run IMO

indeed its also worth noting how settled this month looks like its going to be,

starting cold then cool then something we have not seen in a longtime an azores high pushing ne across the country.

if things continue with the blocking theme spring and summer could be pretty warm this year.

i think the chances of anything wintry are very small indeed looking through the models,

but its lovely sunny fresh morning truely uplifting out there.:yahoo:

away with winter bring on spring and the flowers and warmth thunder hail,

love it.

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Posted
  • Location: Peterborough N.Cambridgeshire
  • Location: Peterborough N.Cambridgeshire

I Thought there would be at least 1 comment on the 00z , It gives lots of opportunity for Snow events in the SE and bitter NE winds from Mid next week with the High Moving North and -10 Uppers. Great run IMO

Like I said yesterday Chris the precip charts are a bit misleading at times. What looks like widespread precipitation is infact very weak and hardly worth commenting on. Also the upper temps are around -8C which to be honest at this time of year will still see temps rise to 5/6C.

Next week looks chilly at times with cloud increasing in E areas as the week progresses. Frost looks likely especially in Scotland but E areas look to remain above freezing due to cloud cover. Beyond and probably turning milder across the UK but possibly turning unsettled especially in the NW with the SE remaining dry.

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Posted
  • Location: Weston Super Mare , North Somerset
  • Location: Weston Super Mare , North Somerset

Like I said yesterday Chris the precip charts are a bit misleading at times. What looks like widespread precipitation is infact very weak and hardly worth commenting on. Also the upper temps are around -8C which to be honest at this time of year will still see temps rise to 5/6C.

Next week looks chilly at times with cloud increasing in E areas as the week progresses. Frost looks likely especially in Scotland but E areas look to remain above freezing due to cloud cover. Beyond and probably turning milder across the UK but possibly turning unsettled especially in the NW with the SE remaining dry.

I understand precipitation rates , But nice to see the High move North instead of South is the point I was making . I am a little confused with the Met office still forecasting rain in the Midlands this afternoon with GFS is having none of it and the latest Satellite Pic confirms what GFS says really.

eurir_sat_201003050900.jpg

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indeed its also worth noting how settled this month looks like its going to be,

Aye, horrible and dry looking:

post-2844-12677822258255_thumb.gif

Almost no rain across the UK; I'm starting to get sick of this continental weather :yahoo: I bet you by July it's lashing with rain though.

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