Winter Model Output Discussion - 06Z 09/02/13 onwards

[Timmytour]

Some may disagree but looking at the link below and ECMWF is more consistent through its run to T+240 than GFS is, by that I mean the 00z and 12z runs, ECMWF follows much more closely on both runs.

Just what that means in terms of the surface weather is yet to be proven but it does lend weight to the general idea from longer range models of a more settled spell with an upper ridge over/close by the UK and a surface high probably somewhere north rather than south of the UK. By how much east or west is rather uncertain.

http://www.netweathe...modelcomp;sess=

also picking up on a comment that GFS is perhaps performing better than ECMWF this winter-not a view I share and the stats tend to support that.

I only have the 6 day verification stats for 500mb for the northern hemisphere but only in January did GFS slightly outperform ECMWF. In December and so far this month ECMWF led by a fair margin.

I think at times over the past week I may have been perceived as portraying the GFS as being more accurate than the ECM. But though I am a GFS supporter, it doesn't mean i think it's more accurate! By way of explanation, to me the GFS will show be how volatile the forecasts are.... the more it comes up with different solutions over different runs, the more I believe our weather will depend upon one or two knife-edge situations which could send things either way.

Hence I'm loathe to support another model showing a consistent output if the GFs is not by and large backing it in most runs.

I would imagine the bigeest verifications come when there is cross-model agreement....maybe on a scale of 7 or more out of ten for a couple of days. Obviously December was a big let down...but I don't think the models agreed for more than a day about that Easterly......with the GFS drifting away from it almost as soon as "THAT ECM" was produced to finally bring it on board.

[london-snow]

Just thought I would re-post this from GP as it seems to fit in with what is being reflected in some of the models tonight

Especially the part in bold, give or take a couple of days!

Posted by Glacier Point on 03 February 2013 - 13:22 in Model Forum Archive

GEFS mean becoming really quite bullish here. Developing anomalous ridge in the North Atlantic (teleconnected to strongly amplified ridge over Alaska) and increasing tendency for +ve heights across the north eastern quadrant. Model seems to be dropping big hints of another injection of westerly inertia into the Pacific sector with consequent downstream ampification. (remember the GWO options - rinse and repeat phases 5-6-7-8 or head down into phase 1?).

We remain under the influence of a cold trough throughout. Out to day 10 and temps below average acoss Europe. GEFS has Switzerland as the core 'low' at 9C below average, but values 2-4C below for the UK. T2 analysis (and cyclonic signal) suggesting little diurnal range - read convective and frontal potential + below average temperatures (do the maths).

If the GEFS mean is anything to go by, there will be another easterly attempt within the 15-20 day timeframe (that's in addition to the one now being modelled) and wouldn't be suprised at all if the models suddenly latched onto a piece of pv dropping round the back of the ridge over Svalbard in the 8-12 day timeframes.

I think I would like the same crystal ball he's using

Unfortunately that post was near 10 days ago & GP has gone quiet since. If i remember he was looking at the back end of Jan ~ Early Feb as our opportunity to see a sustained cold spell. Looks like we have missed that boat.

[rory o gorman]

I would agree with the above statement from london-snow . Being a pro has little advantage when forecasting in the long range especially at this latitude and people do hang on every word and have a habit to ramp the said forecasters comments.

Personally i believe there will be a sustained albeit modified period of blocking, with a scandi high dropping or perhaps cutting off into a Bartlett . overall i don't see uppers under -6 with no clear flow from the P.V and a filling trough over Europe.

[Southern Storm]

Unfortunately that post was near 10 days ago & GP has gone quiet since. If I remember he was looking at the back end of Jan ~ Early Feb as our opportunity to see a sustained cold spell. Looks like we have missed that boat.

Just going off the post I copied, his prediction looks spot on if you ask me, the way i see it, Gp said that he expected the NWP to latch on to the possible scenario of the Pv dropping around the back of the Svalbard ridge in the

8-12 day range,

We are now 9 days on from that post! and we are seeing signs of this being modelled.

Maybe I have my wires crossed as its late.

Edited February 12, 2013 by thunderman24

[Blizzardof82]

Just going off the post I copied, his prediction looks spot on if you ask me, the way i see it, Gp said that he expected the NWP to latch on to the possible scenario of the Pv dropping around the back of the Svalbard ridge in the

8-12 day range,

We are now 9 days on from that post! and we are seeing signs of this being modelled.

Maybe I have my wires crossed as its late.

No I think you have analyzed his thoughts correctly.

[Dave Kightley]

Not much change this morning with GFS slight less amplified and further east with the high bang on top of us pretty much before having a go for Greenland.. Ending with a N flow with easterly not far behind i suspect. Ukmo same with high and the pattern further east then the ECM 12z but good.

Only worry is all the good stuff remains in f.l but the signal is good .

Edited February 12, 2013 by Dave Kightley

[Ryan Dutch Weatherman]

There are realy good chanse with some of the model runs.

Some energy at the wrong place s is going out.

High signals start near Norway/Iceland.Also in the top of the heights.

Ukmo looks ok en building towards the block .

GFS 00z is also looking good. , it wil bring the Nord flow , later on with possible little cold lows from Spitsbergen or the from the weather island Jan Mayen.If this can get trough , it can bring snow with it.

Nogaps at 180 hours comes with a highpressure systeem between Iceland en Norway , with 1030 or 1035 hectopascal.

Near Denmark there is a cold low arrived from the north.This could be effect Brittain.

Gem is puting some heigh pressure at 204 over us .But i think thats over reaction.

As is see all together [ waiting for ECMWF still ] is this the conclusion : NO Strong Atlantik or not at all.

B ; staying cool ,en possible cold weather on his way back later with possible also snow en wintry weather , frost widespread.

So lets wait together for the fore some holy model the ECMWF . I am trilled en exiting.I have a good feeling overal in this.

It could be that we will face in march UK en Netherlands a litlle Nemo [ my opinion en CFS ]

Ok lets stop the analyse me for a while en just wait , with tea.

[Ryan Dutch Weatherman]

There come the latest CFS 18z with the Polar Vortex moving in to the south.

Are we in for someting special weather 3e decade februari en beyond that ?

I think so , but unsure with the models .

[Ryan Dutch Weatherman]

CFS .

Look at this charts again for the 19e run at a row , who can asure me that it can nor happen ?

Mostly it dont happen in march so cold pattern , but in can in fact .

In march 2008 i had at end march 20 cm snow , i think it was pasen , how you call it ? Eastern ?

In 1999 end i think somewere in 2002 [ not sure exact , dont pin me down on the exact data]

i CAN assure you that i had 10 cm snow en other occasion 30 cm in April ! en also -10 .

So it is unlikely , but unlikely doesnt mean it is impossible !

Believe me or do not believe me , its up to everybody for her him self.

Ok ECMWF is running now , lets see en analyse.

[Jason M]

Lots of decent ensemble charts again this morning in FI although all out at 10 days plus as always.

I recall waiting for a train recently and being told it was running several minutes late. After those minutes had passed rather than see the train there was another announcement. This went on for some time until a final announcement that the train was cancelled. I feel this analogy might be appropriate here.

ECM is a little earlier with trying to bring some sort of easterly at 168 hours but it does seem to keep doing this.

In summary, high pressure in charge, average temperatures and a possible easterly some time before Easter :-)

Jason

Edit ECM out to 192 and its going the GH route by the looks of things.

Edited February 12, 2013 by Jason M

[winterof79]

http://www.meteociel...1-192.GIF?12-12 Somethings afoot.

If the ECM 32 dayer follows could be an interesting period

Edited February 12, 2013 by winterof79

[Weather-history]

There is one trend that is evident and that is the charts are becoming more and more blocked. UKMO 0z at 144hrs looks more blocked than the 12Z one or less Atlantic influence. It looks as though we are not going to have an Atlantic zonal dominated 2nd half to February at this stage.

Edited February 12, 2013 by Weather-history

[winterof79]

http://www.meteociel...1-216.GIF?12-12 Awaits the been here in December posts.

http://www.meteociel.fr/modeles/ecmwf/runs/2013021200/ECH1-240.GIF?12-12

Sun would be too strong and the lengthening days would scupper it..............roll on spring

Edited February 12, 2013 by winterof79

[cooling climate]

Lovely ECM run this morning and the GFS is not to shabby either. Detail to be

resolved but they are both promoting northern blocking and another wintry

outlook gains momentum.

Good to see the SSW at work.

[winterof79]

Lovely ECM run this morning and the GFS is not to shabby either. Detail to be

resolved but they are both promoting northern blocking and another wintry

outlook gains momentum.

Good to see the SSW at work.

If i recall,fergie weather did post back in January,that the effects can last up to 6-8 weeks.Something similar.

[That ECM]

http://www.meteociel...1-216.GIF?12-12 Awaits the been here in December posts.

http://www.meteociel.fr/modeles/ecmwf/runs/2013021200/ECH1-240.GIF?12-12

Sun would be too strong and the lengthening days would scupper it..............roll on spring

Been here in dec, must of missed that!!! ECM continuining with some serious blocking to the nw. That would give winter a big finish. Lets watch with interest.

Edited February 12, 2013 by That ECM

[mountain shadow]

Massive potential for a severe cold outbreak on the overnights with high pressure migrating towards Greenland and PV portion dropping into Scandinavia.

Could be busy on here shortly if the trend continues.

[bluearmy]

That shortwave seems keen on the low countries. That pattern delvered our best snowfalls in the se feb and nov 2010. Hope the continental flow will have chilled the surface temps if it arrives like that.

[Ian Brown]

http://www.meteociel...1-192.GIF?12-12 Somethings afoot.

If the ECM 32 dayer follows could be an interesting period

The ECM 32 dayer has been going for that scenario since November, maybe it will finally nail it in late Feb

The models have decent agreement to T144 with the UK under High pressure and energy to the West, which the ECM then subsequently takes South to build pressure at higher altitude, whereas the GFS splits the energy to maintain HP close to the UK.

[Ryan Dutch Weatherman]

Good morning weatherland , en we start immediantely with the update. Ready to rumble ?

As expected ; the MAJOR PROJEKTION from the ECMWF 12z yesterday contineu s today with the 00z.

A great massive outbreak from the Artic towards Brittain en western Europe.

I told many times , dont mark your self to MJO with his false fase 2 en even true it doesnt say alway severthing.

Fasten your seatbells again !

En later i will come back on mine vision mixed with CFS en JMA data for the month of march 2013.

It could be an invasion of Brittain from the army of the Polar Bears

[Craigers]

What im really happy about is that the GFS is some sort on same idea as the ECM now.

This trend seems to be growing and has been showing on and off for the past week.

Wasn't expecting this to happen really

[Ryan Dutch Weatherman]

This is a becoming just a breaking weathermodel news story the ECMWF in particular.

I am really trilled by this chart , look again !.

If the chart wil come out , we could see signifant amount of snow , 50 -90 cm snow in UK en my country as well.

[That ECM]

This is a becoming just a breaking weathermodel news story the ECMWF in particular.

I am really trilled by this chart , look again !.

If the chart wil come out , we could see signifant amount of snow , 50 -90 cm snow in UK en my country as well.

50/90 cm!!! When will you start ramping?!!!!

[Liam J]

Quite ironic that we wait all winter for something epic to turn up and now we may be waving goodbye to winter with the most frigid and severe spell of the last 3 months! Now all we need to see are these epic charts move ever closer towards T0, not asking much then given the last few months! Perhaps we'll get our long awaited rewards this time?

We need something rather more special to deliver as we enter late season which is certainly what the ECM is showing and to a lesser degree the GFS, but both do look broadly similar which is a good sign. Don't put those snow shovels away just yet

I feel sorry for Gavin having to wake up to charts like this....

Lets hope this evolution gains momentum as this is the best route for delivering deep cold, snow and ice days at this stage in the winter.

Edited February 12, 2013 by Liam J

[Severe Siberian icy blast]

Quite ironic that we wait all winter for something epic to turn up and now we may be waving goodbye to winter with the most frigid and severe spell of the last 3 months! Now all we need to see are these epic charts move ever closer towards T0, not asking much then given the last few months! Perhaps we'll get our long awaited rewards this time?

We need something rather more special to deliver as we enter late season which is certainly what the ECM is showing and to a lesser degree the GFS, but both do look broadly similar which is a good sign. Don't put those snow shovels away just yet

I feel sorry for Gavin having to wake up to charts like this....

I agree,

But I've havent really seen many of these deep freezes in fi this winter, yes we had the failed easterly, but we havent had Europe in the freezer this year , so it's good to see this been forecast by the models , now we need consistency now , and to see this move closer , but it's nice to see both the big models on the same page for once . The ECM looks epic in fi , the gfs brings a watered down version , but looks to be heading in the same manor with Europe going very very cold.

Edited February 12, 2013 by Severe Siberian icy blast