General Model Output Discussion:

[Solar Cycles]

Hi Solar,

I think the most important thing at the moment is establishing the cold / severe cold air source, precipitation in these situations can not be forecast acuratly until 24-36 hours out. Although the models do not currently prog much precipitation, I guarantee that some areas will see significant precipitation during this cold spell. As some one has already mentioned, any precipitation that does fall is likely to do so as snow.

The longer the cold spell the more probability of snow fall.

I am being carefull not do get dragged along with all the hype, but in terms of what I have seen from the model outputs, this really is unprecedented. More importantly, people who have been watching the models for a lot longer than me also agree.

Looking forward to the next couple of weeks.

Dave

I agree, that's why I added "as it stands". I have no doubt Eastern areas, and the South East, will do very well out of such a set up. As for the rest of the UK, it will be predominately dry!

[BristolBlizzard]

is the front up north making its way back south yet ! or is it not sure when it will .

[izi]

two things:

1) there is currently alot more precipitation in N england than was forecast, isn't there?

2) can anyone remember a GFS output which remained cold throughout the whole 365hours? I know past 144 is pretty much rubbish, but still amazing to see.

[bluearmy]

http://www.knmi.nl/exp/pluim/vijftiendaagse/index.html

bit colder than yesterdays 00z run with less enthusiasm for an end to the freeze. bit surprised that the precip on the op isnt higher.

[MKN]

the problem there days that people see the charts that are almost identical to those that have brought many great snow events, the thing is these days they dont. Ssts are probably the primary cause but to get a very cold snowy period in this country is much more difficult than in the past. The last 24 hours, had it been 40yrs ago im certain would have gave a blanket of snow quite widely. As for the next 7 days i see the wintry mix slowly clearing up til early hours of new years day followed by largely dry but cold weather

[TEITS]

IT's looking cold yes but not very snowy , no strong north east winds or east winds after friday... Are we getting excited over a long cold dry period? , as i said before no interest unless we get alot of snow in my part of the world. We didn't last time. Show me some charts where snow is possible for us

I already have!

Without wanting to state the obvious but you need the cold in place first before looking for snowfall. Also the trend from the models is to bring an increasing risk of snow into next week which to be honest is what the Met O 6-15 day forecast said yesterday. The model runs this morning are probably the best I have ever seen for the +144/+168 period. I really think you need to appreciate what your seeing rather than looking for a strong flow from the E.

Also if I think back to my childhood days in the 80's then cold spells never used to bring instant heavy snow. Often I experienced a spell of frosty, cold weather before the snow arrived.

[nick sussex]

Still very good support for the ecm operational run on todays De Bilt ensembles, for days 8-10 though it is one of the warmer options for the Netherlands! The control run is superb also and keeps it below freezing for the next 15 days.

http://www.weerplaza.nl/15daagseverwachting/default_pluim.asp?r=midden

Edited December 30, 2009 by nick sussex

[TEITS]

the problem there days that people see the charts that are almost identical to those that have brought many great snow events, the thing is these days they dont. Ssts are probably the primary cause but to get a very cold snowy period in this country is much more difficult than in the past. The last 24 hours, had it been 40yrs ago im certain would have gave a blanket of snow quite widely. As for the next 7 days i see the wintry mix slowly clearing up til early hours of new years day followed by largely dry but cold weather

Sorry but that is wrong.

If this was 40yrs ago then exactly the same would of happened. The reason yesterday didn't bring widespread, heavy snow is because the front wasn't meeting a very cold pool of air.

I mean this in the nicest possible way but if anyone cannot see how fantastic the model output currently is then im afraid your misreading the models.

[stewfox]

Sorry but that is wrong.

If this was 40yrs ago then exactly the same would of happened. The reason yesterday didn't bring widespread, heavy snow is because the front wasn't meeting a very cold pool of air.

I mean this in the nicest possible way but if anyone cannot see how fantastic the model output currently is then im afraid your misreading the models.

Have to agree if the synoptic pattern was the same 40 years ago then the outcome would be the same.

Although how are the seas around the uk now ? In line with 'average' temps ?.

[nick sussex]

Sorry but that is wrong.

If this was 40yrs ago then exactly the same would of happened. The reason yesterday didn't bring widespread, heavy snow is because the front wasn't meeting a very cold pool of air.

I mean this in the nicest possible way but if anyone cannot see how fantastic the model output currently is then im afraid your misreading the models.

Agree with you Dave, i just wonder what sort of output would please some folk! We've both been on here for years and i think you would echo my sentiments that this is the best output we've ever seen especially as it is showing within 144hrs and not stuck at the far reaches of GFS FI with no hope of verifying.

People just need to be patient, lets get the cold first and see how it pans out in terms of snow.

[Solar Cycles]

Sorry but that is wrong.

If this was 40yrs ago then exactly the same would of happened. The reason yesterday didn't bring widespread, heavy snow is because the front wasn't meeting a very cold pool of air.

I mean this in the nicest possible way but if anyone cannot see how fantastic the model output currently is then im afraid your misreading the models.

Certainly agree with you on this Tetis, but for Western areas Easterlies rarely bring snow, except for when the Atlantic tries to spoil the party. That NE would be the best bet IMBY, but one thing we will all have, is extremely low minima's, and daytime temps struggling to get above freezing in all areas!

[TEITS]

Still very good support for the ecm operational run on todays De Bilt ensembles, for days 8-10 though it is one of the warmer options for the Netherlands! The control run is superb also and keeps it below freezing for the next 15 days.

http://www.weerplaza.nl/15daagseverwachting/default_pluim.asp?r=midden

The ensembles are just incredible. Note how the mean below freezing has been extended compared to yesterdays 0Z.

Take note everyone, to have the ECM ensemble mean at 0C has been a challenge in recent years. However just look at how low the mean is and for how long!

http://www.knmi.nl/exp/pluim/vijftiendaagse/index.html

The control run is just silly!

[Duane S.]

Sorry but that is wrong.

If this was 40yrs ago then exactly the same would of happened. The reason yesterday didn't bring widespread, heavy snow is because the front wasn't meeting a very cold pool of air.

I mean this in the nicest possible way but if anyone cannot see how fantastic the model output currently is then im afraid your misreading the models.

Absolutely right. SST's etc etc were absolutely nothing to do with it being a mainly rain event, the cold air wasn't mixed in with the front. I am continually amazed why some people, excluding those who are new and learning, fail to see this simple fact. The charts couldn't have highlighted it any better than they already did, they even colour code it for you for goodness sake!

[TEITS]

Here come the snow showers for E areas on Friday.

http://www.wetterzentrale.de/pics/Rtavn604.png

Always maintained that for E Anglia/SE Friday is the best convective day for this area. However the convection of E Scotland/NE England looks even more promising into the weekend!

[jethro]

people have been saying cold 850`s etc yes it will snow if these charts come off it will be great, for weeks!! yesterday definately snow !! guess what, wrong type of cold air no snow !! i think some are just hyping things up to keep interest on here, and others are talking bull so deep you can walk in it ! come on people leave it to the known members on here. they know who they are, lets have the old dependable net weather back not this boll--s

Folk can only talk about what the models are showing surely? Currently it's looking amazing, last minute details of "will it snow" are well, last minute. Aren't they?

[Frosty.]

One corner of england is still almost tropical compared to the bulk of the uk, southwest england with a sw breeze at 20mph and a temp of 10c but cold air winning everywhere during the next few days as the front in the south weakens and the NE'ly sweeps across all areas. Very wintry 00z output this morning and not FI fluff either, bitterly cold conditions look like digging in until the end of next week at least.

Edited December 30, 2009 by Frosty039

[yamkin]

Joe B astardi was scoffed at and even called a "crank" over his European winter forecast. He looks less of a "crank" when you see this

Manchester 2m temp ensembles are very cold, they don't even get above 5C until after the 11th January and even then they are only handful that does.

http://91.121.93.17/pics/MT2_Manchester_ens.png

Mr_Data, You are totally correct about Joe B. He has really got this winter nailed to a T IMO. Steve Murr's & my signatures reflect Joe B's winter message.

Quick question Mr_Data, would you know what model(s) Sky News forecasters use?

[Duane S.]

Folk can only talk about what the models are showing surely? Currently it's looking amazing, last minute details of "will it snow" are well, last minute. Aren't they?

Well put.

This is a model discussion thread and we are discussing the models, which just so happen to look absolutely fantasic, at the moment at least...

[snowray]

I agree, that's why I added "as it stands". I have no doubt Eastern areas, and the South East, will do very well out of such a set up. As for the rest of the UK, it will be predominately dry!

Not necessarily, I am so used to near misses down here for snowfall its almost a joke. Yes it looks like its going to get cold or very cold, but could end up pretty dry as well. This morning for example there should have been widespread snow north of the M4, but its all well North and only snowing in the mountains of N Wales and N England, Scotland seems to have more in the way of Snow showers though, is this not more along the lines of what GFS was showing a couple of days ago?

The 06z clearly then shows that when the cold air finally digs back South, most of the PPN is gone, even the heavy streamer that has been showing up Thurs/Fri for SE and EA has virually gone with just flurrys away from the coasts.

We are then left looking to the SW which is currently a 50/50 as to weather it will make it even as far as Cornwall.

Edited December 30, 2009 by snowray

[Cecil Hogmanay Melchett]

GREAT models this morning with the exception of GEM.

There is a critical period for this upcoming cold spell and thats around 96hrs mark,most of the models have that lp to the SW digging south but GEM doesn't,and that spells trouble.

I dont want to knit pick but thats the only potential fly in the ointment this morning.

Lets hope the gem is having a wobble and the other models dont follow it!

ecm/ukmo/gfs look amazing tho'.

[kold weather]

Utterly insane 0z GFS, cold the whole way through the run and still no sign of a change at the end, insane run!

The 0z ECM is pretty crazy as well, 216-240 would be bitterly cold, you just don't often get a set-up that cold, esp nowdays!

Anyway lets wait to see what the 06z shows, it can't get much better for sustained cold then the 0z though gotta be said...

[TEITS]

We are then left looking to the SW which is currently a 50/50 as to weather it will make it even as far as Cornwall.

We don't want this to hit the UK.

This LP is one of the jigsaw pieces that is responsible for pulling in a much colder NE,ly flow from +144 onwards.

[doublebarrel]

Well put.

This is a model discussion thread and we are discussing the models, which just so happen to look absolutely fantasic, at the moment at least...

i totally agree with what yourself and Jethro say. but if `the models `are saying it then why is it not happening in real time ? yes it is difficult, but in this day and age of technology maybe better eh

[Guest North Sea Snow Convection]

Looks as though Jan 2010 is set to break the mild Jan winter bogeyman - quite a way to do it as well! lol!

The charts on offer across the board in realtime (as in realistic time period I mean), are the type that have cropped up previously on GFS fantasy outputs that have sent the model thread off on a seven page rampage of hyperbole!

Makes you think of all the pages and pages of discussion on n-w over the last few years about synoptical possibilities, and what can and can't happen these days. Looks like what was dubbed wishful thinking and hankering after the good ole days at times, is becoming the reality it was intended to mean

The GEM would remain bitterly cold all the way through its output imo

Edited December 30, 2009 by North Sea Snow Convection

[Frosty.]

GREAT models this morning with the exception of GEM.

It's ironic that the GEM has dropped the ball having been the one model which was showing a prolonged wintry set-up but hopefully it will just be a blip.