The GFS 18hz Discussion Thread

[J10]

Please continue your general comments on the models here.

[PB22]

Obviously its been a while since I have studied the charts in detail, but looking at them this evening on the excellent Net-Weather Extra section, I can see a cold start to the week with a Greenland High slowly declining. Fronts then try to approach from the west, but they could be stopped by rising pressure to the east. Some very exciting charts there I thought, and some intriguing model watching to do.

[Paul]

Cheers Paul, fun times ahead!

Looking at the early stages of the 18z, a slight accelleration of the colds move southward tomorrow from the 12z.

18z

12z

[s4lancia]

This has got ALL the ingredients of being a bit special. Of course it could just as easily be a damp squibb.

Everything rests on pressure to our east. If it can build quickly enough then it will be VERY interesting and the chance remains that this could happen.

The Countryfile forecast will be of great interest. I bet even now they are scratching their heads trying to put it togther!

[Toppler]

Off topic so mods delete- But Hi to Paul B, just to say your model posts were great and I learnt a hell of a lot from them.

Cheers.

[PB22]

Thanks Toppler, kind of you to say so.

18Z out to T+90 now, and pressure is starting to rise over Scandinavia again. And the whole general pattern is ever so slightly further west I think.

EDIT: Indeed its looking better for chances of the cold weather persisting with pressure now progged to be at 1025mb over Scandinavia by T+96, and the heights are also looking better.

[Snowly does it]

Core of the jet slightly further south and angled more to the south of east? T90

850 -5s in roughly similar stte to the 12z run although perhaps weaker around the southern area.

[BARRY]

the -5 on 850pha is down over devon on tuesday for a change

[Matty M]

Cold air being pushed out though before the fronts arrive..

Very similar to the 12z though so expected but not the same as the UKM and ECM take on things

Pressure upto 1030mb over Scandy at 114hrs

Cold being pushed back into eastern England!!!!!

[PersianPaladin]

QUOTE(Paul B @ 3 Feb 2007, 10:02 PM) <{POST_SNAPBACK}>Thanks Toppler, kind of you to say so.

18Z out to T+90 now, and pressure is starting to rise over Scandinavia again. And the whole general pattern is ever so slightly further west I think.

EDIT: Indeed its looking better for chances of the cold weather persisting with pressure now progged to be at 1025mb over Scandinavia by T+96, and the heights are also looking better.

[PB22]

One heck of a cold pool out to the east if we were to tap into that then we "could" be onto something special.

[Matty M]

Basically things are great at the moment expect the little shortwave that moves in during Wednesday ruins things abit by pushing the cold air out before the actual weather systems try and meet against the building Scandy high. Still very nice for east UK

[Snowly does it]

[quote name='Matty M' date='3 Feb 2007, 10:08 PM' post='909135'

Cold being pushed back into eastern England!!!!!

[PB22]

--><div class='quotetop'>QUOTE(Paul B @ 3 Feb 2007, 10:02 PM) <{POST_SNAPBACK}></div><div class='quotemain'><!--quotec-->Thanks Toppler, kind of you to say so.

18Z out to T+90 now, and pressure is starting to rise over Scandinavia again. And the whole general pattern is ever so slightly further west I think.

EDIT: Indeed its looking better for chances of the cold weather persisting with pressure now progged to be at 1025mb over Scandinavia by T+96, and the heights are also looking better.

Indeed....but at the cost of significant snow?

Looking at this run up to T+114 I would say look east rather than look west.

[Matty M]

Hubba Hubba at 120hrs.. close to something really special

Pressure nearing 1035mb over Scandy weather systems failing to make progress

JMA from a few days ago doesnt look so unplausable now!

[rdt123]

Basically things are great at the moment expect the little shortwave that moves in during Wednesday ruins things abit by pushing the cold air out before the actual weather systems try and meet against the building Scandy high. Still very nice for east UK

Isnt it amazing how that scandi high has appeared over the past 24 hours. A 1030 high is now centred over norway at T+114

[Pennine Ten Foot Drifts]

QUOTE(Paul B @ 3 Feb 2007, 10:02 PM) <{POST_SNAPBACK}>Thanks Toppler, kind of you to say so.

18Z out to T+90 now, and pressure is starting to rise over Scandinavia again. And the whole general pattern is ever so slightly further west I think.

EDIT: Indeed its looking better for chances of the cold weather persisting with pressure now progged to be at 1025mb over Scandinavia by T+96, and the heights are also looking better.

Indeed....but at the cost of significant snow?

We shall see.

Exactly, it's starting to look like a possible scenario is that the fronts are stalled to such an extent that they hardly get over England to any great extent, until of course the milder air actually does win, so what we end up with is dry cold air hanging around for longer , but any proper precipitation only arrives with the milder air, later.

[Hillian]

Low pressure from Atlantic stalling even more by 120

[Matty M]

At 132hrs a Scandy high of 1037mb is centered over southern Norway, Easterly winds feeding into England.. Front turning to snow for eastern Ireland.

[Nick F]

An interesting 18z so far, with what initially looks like the colder sub -5C 850s being pushed East as the Atlantic system advances, however by t+120, the Scandi high builds and a cut-off low slides to the SE of the UK dragging in an Easterly flow and the sub -5C 850s back west again, though this stalls the frontal system over the West which is a downside compared to the 12z.

Edit, the cold sub -10C 850s over Scandi are backing West!!!

http://www.wetterzentrale.de/pics/Rtavn1322.png

[Matty M]

Maybe a few of these required

[TEITS]

-->

QUOTE(Paul B @ 4 Feb 2007, 12:09 AM) <{POST_SNAPBACK}>

One heck of a cold pool out to the east if we were to tap into that then we "could" be onto something special.

Great to see you on here again Paul.

This Scandi HP has got me very curious indeed especially how the models are handling this. Over these past few days the models have hinted at this moving being closer to the UK. Now on the 18Z this is ridging further NW to an extent where E England is pulling a SE,ly in.

What in your opinion is the chances of this HP having such an effect where the Atlantic is unable to progres across the country and dare I say it an E,ly pushes across the UK.

[PersianPaladin]

SATSIGS now on standby.

Tremors imminent.

[Cumulonimbus Tower]

Enjoying this 18z very much so far. What a great shape to the scandi high at 132 eh?

[J10]

Indeed this has happened in recent years, just a slow seep in of milder air usually from the north west.

Some of the Faxes are out From 12Hz today.

http://www.wetterzentrale.de/pics/brack0a.gif

http://www.wetterzentrale.de/pics/brack1.gif

http://www.wetterzentrale.de/pics/brack1a.gif

http://www.wetterzentrale.de/pics/brack2.gif ( A VERY MESSY CHART)

More Due Later.