Model Output Discussion - Sunday 20:35--->

[Cal]

http://91.121.94.83/modeles/gfs/run/gfsnh-0-114.png?6

Much better, the shortwave is further east which may allow both the uk high to retrogress north and the artic high south . The atlantic is a tad more west on this one.

[Guest North Sea Snow Convection]

Well im going to sit on the fence with this one because we have seen far too many changes in the model output to have any confidence in the outcome.

I would say its safe to assume its going to turn more settled, colder with fog and frost. However if your after deep cold, snow then consider this as a bonus because at the moment dry, frosty weather is the favourite.

Morning Dave

I think many of us can agree with that. I have got to say, the end of this dreadful stormy south westerly spell of weather will be a huge relief and big reason to cheer in itself. Still today especially to have to endure though, but by the second half of the week some blissful peace and quiet arrives

I especially welcome and love an easterly at any time of year - it could be though that this may need another opportunity further on. I think overall the high pressure is going to stay too close to the UK to get the coldest air - although the current (and predictable) model uncertainty rules nothing out of course.

No need for any despondency about things at all though I think. In the circumstances, a change of pattern from the mid November one is great in itself.

[Lewis]

http://91.121.94.83/modeles/gfs/run/gfsnh-0-114.png?6

Much better, the shortwave is further east which may allow both the uk high to retrogress north and the artic high south . The atlantic is a tad more west on this one.

I thought the atlantic was a little more east on this one, hence why i thought it was a downgrade, i expected the atlantic gates to open and flood in again.

Looking good

[Cal]

Artic floodgates to be unleashed?

http://91.121.94.83/modeles/gfs/run/gfsnh-1-126.png?6

[cooling climate]

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Posted Today, 08:57

With such large discrepancies between the ECM and the UKMO charts at t144 on the

n/hemisphere charts regarding blocking over our side of the Arctic means things are

far from settled.

Lack of data and monitoring equipment is a problem as we know when it comes to modeling

the high Arctic but I do think that the ECM has been way over progressive in breaking down

the block.

If you look at the time frame t120-t144 where a piece of the vortex cuts into the block which

has a knock on effect of shunting everything southwards in our direction, looks completely

implausible to me.

Steve Murr may well turn out to be correct in his fears of shortwaves running through the

block and spoiling the party we shall see but the UKMO is not so keen on this idea, neither

am I.

http://www.meteociel...72&mode=1&map=1

The ECM looks to be on its own regarding the vortex energy breaking down the heights.

This should be a cracking run now.

[nick sussex]

This disagrees with the ecm which is good news and thankfully no movement at all by the gfs 06hrs run towards the ecm.This looks quite similar to the ukmo.

[Cumulonimbus Tower]

http://91.121.94.83/modeles/gfs/run/gfsnh-0-114.png?6

Much better, the shortwave is further east which may allow both the uk high to retrogress north and the artic high south . The atlantic is a tad more west on this one.

Yup, look at the heights flooding into Svalbard

[Anti-Mild]

Better heights between Greenland and Svalbard at +120 on the 6z, as well as a better Jet profile. It'll be interesting to see how things shape up at around +240 on this run, it should be a cracker!!

[Cecil Hogmanay Melchett]

06z looks a cracker .

And has all the latest data,so,well you are only as good as your last run!

Look at that plume heading for the Artic!!

[snowray]

Just had a quick look at Ian's Dec 05 Easterly and it is a prime example on how quick things can change when there is high pressure over the UK

we went from this on Christmas day

To this on the 27th

I think that is exactly what will happen in this case . It will turn up in the T-96 chart at the end of the week or over next Weekend.

Yes, would be nice to see. Thats why I dont pay much attention past T120 apart for possible paterns, since there is so much that can happen in the meantime, and all these pesky SWs to contend with.

[snowmadchrisuk]

I thought the atlantic was a little more east on this one, hence why i thought it was a downgrade, i expected the atlantic gates to open and flood in again.

Looking good

Lesson 1 , as the charts come out , say 6z is out to +96 click on to the +108 chart and see what oz shows for the same time period , look for the yellows and orange around Greenland and Iceland , this morning you can clearly see how much further west it is. Also look at the H500 charts it is easier to see what is happening.

Edited December 7, 2009 by snowmadchrisuk

[TEITS]

No need for any despondency about things at all though I think. In the circumstances, a change of pattern from the mid November one is great in itself.

Morning Tamara.

I think some members need to appreciate what we are seeing in the reliable timeframe rather than F.I. The chart below is stunning at +126 which is very similiar to the UKMO. Certainly beats some of the synoptics I have seen in previous Decembers!

http://www.wetterzentrale.de/pics/Rtavn1261.png

[Lewis]

Lesson 1 , as the charts come out , say 6z is out to +96 click on to the +108 chart and see what oz shows for the same time period , look for the yellows and orange around Greenland and Iceland , this morning you can clearly see how much further west it is. Also look at the H500 charts it is easier to see what is happening.

Thanks mate,

I'll take note of that

[Cumulonimbus Tower]

06z looks a cracker .

And has all the latest data,so,well you are only as good as your last run!

Look at that plume heading for the Artic!!

And the cold air flooding south over Scandi!

[Lewis]

High pressure filling

Is that a good sign?

[DAVID SNOW]

Morning Tamara.

I think some members need to appreciate what we are seeing in the reliable timeframe rather than F.I. The chart below is stunning at +126 which is very similiar to the UKMO. Certainly beats some of the synoptics I have seen in previous Decembers!

http://www.wetterzentrale.de/pics/Rtavn1261.png

Perhaps a slush puppy then

[snowmadchrisuk]

If the High get's any further North at +144 we will have a Euro High in the Arctic Come on my Son.

[Guest North Sea Snow Convection]

Morning Tamara.

I think some members need to appreciate what we are seeing in the reliable timeframe rather than F.I. The chart below is stunning at +126 which is very similiar to the UKMO. Certainly beats some of the synoptics I have seen in previous Decembers!

http://www.wetterzen...s/Rtavn1261.png

Agree wholeheartedly!

I made the point recently about the UKMO model often being the one that is least keen on developing these cold spells. This time around however, so far, it has been consistent in wanting to develop the best -AO set-up - whilst the other models crash and burn. The current GFS is much closer to the UKMO though which is good to see this morning. Although I remain cautious about a proper cold spell, the chance is certainly there!

The coldest air needs that trigger to come south westwards in the t144 to t168 period = that is going to be the hardest part and because it is still some way off in reliable model terms there is some way to go yet before the sledges can come out .

Edited December 7, 2009 by North Sea Snow Convection

[snowmadchrisuk]

Agree wholeheartedly!

I made the point recently about the UKMO model often being the one that is least keen on developing these cold spells. This time around however, so far, it has been consistent in wanting to develop the best -AO set-up - whilst the other models crash and burn. The current GFS is much closer to the UKMO though which is good to see this morning. Although I remain cautious about a proper cold spell, the chance is certainly there!

Snow chance by +156 .

[Lewis]

A BEAST HAS FORMED

[snowray]

Better heights between Greenland and Svalbard at +120 on the 6z, as well as a better Jet profile. It'll be interesting to see how things shape up at around +240 on this run, it should be a cracker!!

Looking very good indeed upto T150 with those hight rises, the only purpose of the Euro high was to block the Atlantic long enough while this could happen then naff off, NOT move North over the UK then back South again after a week or two.

Edited December 7, 2009 by snowray

[Eugene]

Yes a better run than GFS 00Z with a very deep cold pool of air just to our northeast towards the end but very similar synoptically.

I`m looking for a sustained average to below average settled spell, short term fixes do nothing for me, i look at the long term picture not just brief snowy breakdowns followed by more rain

[Lewis]

Wake me up when;

Comes off

[TEITS]

This is turning into a Carlsberg run!

http://www.wetterzentrale.de/pics/Rtavn3002.png

Some need to be wary in what they wish for. If that pool of bitter cold did make its way to our shores then it could knacker your xmas shopping trips!!

Personally im focussing on just +144 because even this timeframe isn't resolved yet as the 0Z/06Z illustrate.

[D KARLSON]

still a lot of inconsistency in the models though UKMO and GFS agree i would advise to hang fire on any winterwoderland dreams just yet ,although there is potential from what are quite rare charts these days ,but a lot of firming up is required on any exact outputs.

What we really need is some plain good luck to allow a promising situation to actually bare fruit ,tonights charts should help things a little ,what we need is the cold air to become established ,which looks likely to occur and then some milder air to try and push back in and create a battleground with stalling weather fronts ,this is a possibility although we havent seen these situations for many years and perhaps maybe more than a week away from seeing this .

Anyway keep a close eye on this and see how it develops