Winter Model Discussion - The Hunt For Cold - 12th Dec

[PubliusEnigma]

Awful ECM at +240.

http://www.meteociel...H1-240.GIF?12-0

The pattern over recent days for +240 and beyond really has been woeful with a positive AO/NAO, PV moving into Greenland.

In some way with a polar vortex returning, the Atlantic could reset so to speak, with fast moving depressions rather than the slow moving

affairs we've had during the summer and autumn where low pressure centres drop off the Jet and wonder within the vicinity of the UK.

If we can get a reset, without he Bartlett forming, we've a chance possibly by the time we get to Mid Jan perhaps. The long range forecasts

for a cold December are very much in doubt now if the latest outputs are to be believed.

[nick sussex]

I know people think the ECM might not be upto much but its far better than the GFS.

And there are a few chances to bring some interest, the GFS has zero interest from start to finish.

[BLAST FROM THE PAST]

Just watched spotlight on BBC and the forecaster said that he'd seen something for the first time. A singular LP that covered and controlled the whole of the North Atlantic. Interesting piece of info. Wonder if JH has seen such a thing or other very seasoned campaigners. Its coming alright.....from the WEST.

BFTP

[Snowly does it]

I know people think the ECM might not be upto much but its far better than the GFS.

And there are a few chances to bring some interest, the GFS has zero interest from start to finish.

Crumb of GFS comfort, the ensembles are not as terrible as the operational with some potential interest in te few days before Christmas. Oh we'll, that's the most positive thing I can find.

[Gibby]

Good evening. Here is my report on the 12z output from GFS, UKMO and ECM for today Wednesday December 12th 2012.

For the first time since doing these reports this season All Models look much the same throughout the duration of the run with very little point in describing specific day to day events from each run. Instead I will tonight lump all the output together with just a Summary of how things pan out over the two weeks.

The current cold weather is living on borrowed time as the cold if light SE flow continues to feed cold air over Britain with some frost and patchy freezing fog the main events of the night hours. Tomorrow will see the last of the cold and sunny days for some considerable time as this report is testament too with the first band of cloud approaching Southern Britain later tomorrow. Then overnight tomorrow wind and rain will sweep into the SW and flood NE over the whole UK over the daytime on Friday falling as snow for a time on Northern hills. Clearer and showery weather will follow which lasts throughout the weekend with the heaviest and most prolonged rain likely for SW areas and the brightest conditions in the NE after the rain passes. Thereafter, the rest of the period from all of the models show a continuation of relatively mild and unsettled weather with spells of sometimes heavy rain followed by showers continuing uninterrupted over the period. Some short drier and brighter interludes will occur for short periods as brief ridges cross East.

The GFS Ensembles show a typical flat and zonal pattern over the UK through its entire run. The 850 temperatures remain close to average when taken as a whole with plenty of rainfall shown indicative of Low pressure passing over or to the NW of the UK.

The Jet Stream shows the main thrust of the Jet pushing East over the Atlantic and entering France. Later next week the flow buckles and ridges around the Greenwich meridian taking it NE over Britain then back SE over Europe, indicative of pressure rising to the South of the UK.

In Summary a milder spell is on the way. Once arrived the milder and unsettled weather looks set to last up to and probably including the Christmas period. There will be rain at times for all, quite a lot of it at times in the SW inparticular. Temperatures will generally stay close to normal or probably rather mild at times later in the South as we approach Christmas and warm sectors pass through. The likeliness of any wintry weather over the model run period looks very remote tonight.

[PubliusEnigma]

I know people think the ECM might not be upto much but its far better than the GFS.

And there are a few chances to bring some interest, the GFS has zero interest from start to finish.

The worry with the GFS Nick, is it's been the formhorse this winter picking out the upcoming trends out in FI.

With a few wobles along the way, before bringing the trend back into line as it nears the higher resolution outputs.

Christmas eve is ghastly with Early May temps if this is to be believed.

[Snowly does it]

The worry with the GFS Nick, is it's been the formhorse this winter picking out the upcoming trends out in FI.

With a few wobles along the way, before bringing the trend back into line as it nears the higher resolution outputs.

Christmas eve is ghastly with Early May temps if this is to be believed.

It doesn't even need to be much of a form horse really, high pressure over Hudson preventing WAA, blocking Siberian high too far east and no undercutting due to HP over Europe with a ridging Azores providing a ski lift for LP..... The forecast almost writes itself!!

In other words, need one of those ingredients to change, and the more the better

Edited December 12, 2012 by snowmaiden

[nick sussex]

The worry with the GFS Nick, is it's been the formhorse this winter picking out the upcoming trends out in FI.

With a few wobles along the way, before bringing the trend back into line as it nears the higher resolution outputs.

Christmas eve is ghastly with Early May temps if this is to be believed.

Yes it did okay with picking up the easterly and shortwave which the others followed sadly they were led up the garden path,as were we all.

In this instance though its been lagging behind with the upstream pattern and has backtracked several times over the last few days.

But overall we're splitting hairs between which is the least worse output, the ECM is not great but better than the GFS, with the PV on the move we can just hope it sets up in Scandi and not Greenland, otherwise my prozac hotline will be overwhelmed!

[PubliusEnigma]

Yes it did okay with picking up the easterly and shortwave which the others followed sadly they were led up the garden path,as were we all.

In this instance though its been lagging behind with the upstream pattern and has backtracked several times over the last few days.

But overall we're splitting hairs between which is the least worse output, the ECM is not great but better than the GFS, with the PV on the move we can just hope it sets up in Scandi and not Greenland, otherwise my prozac hotline will be overwhelmed!

Recent experience shows the PV moving to Siberia is of little use to us. As the Northern blocking didnt want to come our way and even a weak

atlantic was able to limit cold spells to 2 or 3 days at a time. As you say the PV locating over finland or Western Russia would, IMO be the preferred location.

What I find so damned irritating is the Greenland High was there from April through to October almost constantly, then when you need a favour, it cant even

develop hights even with the PV gone elsewhere

[mountain shadow]

Are we into negative figures out of ten yet Nick?

[Frosty.]

Yes the models are flipping us back into normal uk weather following the awful handling of the siberian high and all the other pieces of the jigsaw it was putting together for a prolonged cold outlook that has now gone up in smoke. We are now reduced to scratching around in FI for some air cool enough to bring a bit of wet snow to the scottish mountains. The ecm and gfs 12z show a mostly average to mild outlook until the christmas holidays, maybe until the new year even..oh dear.

[latitude]

After a brief warm up for some over the weekend colder air once again filters back over the UK during next week, just as we lose one low another begins to head our way at t144

With the colder air any precipitation over high ground in the North could well fall as snow

That area of high pressure along the east coast of America isn't doing us any favours at the moment

Cant really see any colder air filtering back, just looks very much average to me.

[PubliusEnigma]

Yes the models are flipping us back into normal uk weather following the awful handling of the siberian high and all the other pieces of the jigsaw it was putting together for a prolonged cold outlook that has now gone up in smoke. We are now reduced to scratching around in FI for some air cool enough to bring a bit of wet snow to the scottish mountains. The ecm and gfs 12z show a mostly average to mild outlook until the christmas holidays, maybe until the new year even..oh dear.

Anyone seen Joe B's latest take on the next 2 to 3 weeks ?

[BLAST FROM THE PAST]

There is always Nibiru and 21/12/12.......about the same chance as massive blocking from east linking to Greenland bringing a prolonged freeze to our shores...lol. Never mind, Christmas is coming

BFTP

Edited December 12, 2012 by BLAST FROM THE PAST

[Weather-history]

Recent experience shows the PV moving to Siberia is of little use to us.

I don't think the PV has moved to Siberia, the main core is to the north of Alaska and Yukon region.

[nick sussex]

Are we into negative figures out of ten yet Nick?

Lol! yes my full review will be out after the ECM ensembles, expect lots of silly analogies, desperate stabs at humour, at least we don't have to talk about the Russian high, flattered to deceive once again and good riddance to it, if theres one thing I hate its that false hope giver!!!

And yes my optimism rating will be out, probably together with a few additions.

[SouthPennine88]

Yes the models are flipping us back into normal uk weather following the awful handling of the siberian high and all the other pieces of the jigsaw it was putting together for a prolonged cold outlook that has now gone up in smoke. We are now reduced to scratching around in FI for some air cool enough to bring a bit of wet snow to the scottish mountains. The ecm and gfs 12z show a mostly average to mild outlook until the christmas holidays, maybe until the new year even..oh dear.

I didn't think the models went as far as the new year yet or am I mistaken?

[Iceni]

Could someone explain why when the models were predicting an icy/snowy Christmas and more or less changed overnight to the opposite a week ago, why people are talking about no more cold until mid January which is over a month away?

Surely the models could do a somersault next week and winter's back on track Christmas new year onwards. I don't understand why people take the models so seriously — is there some physical caste iron reason why the next month is going to be dire or is it just the models which say so?

Edited December 12, 2012 by Iceni

[Gustywind]

Quick question, has a prolonged v.cold spell via a Russian high ever happened? Most of the best easterly spells I can remember have come from a Scandi high, all we seem to get from the Russian high are false promises of easterly riches?

As far as the models go not much positives to take from recent outputs, the beast from the east has been beaten into submission by the pest from the west. Can't see any return to cold now pre Xmas, and not for quite a bit longer than that if the vortex ends up near or over Greenland.

[Frosty.]

I didn't think the models went as far as the new year yet or am I mistaken?

Getting close to the new year now from the gfs, good riddance to that pesky russian high, it was useless.

[SilverWolf]

Just watched spotlight on BBC and the forecaster said that he'd seen something for the first time. A singular LP that covered and controlled the whole of the North Atlantic. Interesting piece of info. Wonder if JH has seen such a thing or other very seasoned campaigners. Its coming alright.....from the WEST.

BFTP

Do you simply mean the LP or is that a big hint? If a massive LP is in the Atlantic can it draw much colder air from the north not usually associated with normal LPs? Limited knowledge, sorry if a stupid question.

Edited December 12, 2012 by SilverWolf

[Froze were the Days]

This was always going to happen (more mobile Atlantic conditions) once LP became established in mid-Atlantic unfortunately we need a whole 'pattern change' to re-establish cold and unfortunately it looks like that will 'see off this month' with an increasingly west and then maybe south westerly jet, as long as this doesn't continue into January I won't be too bothered.

By the way early December cold rarely leads to a white xmas so glad I didn't get carried away with the propaganda.

[Snowly does it]

Do you simply mean the LP or us that a big hint? If a massive LP is in the Atlantic can it draw much colder air from the north not usually associated with normal LPs? Limited knowledge, sorry if a stupid question.

With any LP in the Atlantic we need it to cross us, or better still undercut us as the cold air will always be drawn down the western flank. If its in the Atlantic it can be any size it wants, it's of no use to us for cold as we're stuck on the east of it.

[SouthPennine88]

Getting close to the new year now from the gfs, good riddance to that pesky russian high, it was useless.

Ahh I see ... perhaps a Russian High isn't the most trustworthy of delivering cold. (although temperatures didn't get above -1 here today).

I always look for Greenland blocking for cold spells ... although of course this isn't evident within range just yet!

I shall not be fooled though ... if we kept assuming that the mild would continue after the model runs have ended (in this instance, up until new year), then we are in other words never ever going to see an end to the average/mild output are we?!

It's always going to change sometime

[Frosty.]

at least we don't have to talk about the Russian high, flattered to deceive once again and good riddance to it, if theres one thing I hate its that false hope giver!!!

Yes nick I couldn't agree more, time to put this horrible episode behind us and move on, the models show mediocre fayre for the next 2 weeks plus and now i'm concerned about longer range prospects into the new year and beyond, time to wipe the slate clean and start again I think.