Winter Model Discussion - Cold Hunting - 20th Dec

[Weather Boy]

Can I please ask that with out any Strat Warning, would we have any prospects of possible cold? Genuine question

As nobody has answered this post I will. The answer is yes. In his scepticism of the SSW theory, The Eye in the Sky pointed to December 2009 which brought freezing conditions and heavy snow to some places without any significant strat warming at all let alone a SSW.

I think the true position is that a SSW increases the chance of cold but they are nowhere near 0% without it just as they are nowhere near 100% with it.

Edit: sorry BA did answer this but hopefully my post is a more literal answer to the question.

Edited December 22, 2012 by Weather Boy

[bluearmy]

Not really BD - sorry.

Naefs 12z quite different to 00z. In fi, uppers for london some 4c higher. Anomalys also dissimilar in both placement and intensiity. Naefs not noted for swings in output within a day so caution remains the watchword into week 2.

[I remember Atlantic 252]

any similarities?.....

Ay, Xmas Day 1990 falls on a tuesday, same as this year

[bluearmy]

As nobody has answered this post I will. The answer is yes. In his scepticism of the SSW theory, The Eye in the Sky pointed to December 2009 which brought freezing conditions and heavy snow to some places without any significant strat warming at all let alone a SSW.

I think the true position is that a SSW increases the chance of cold but they are nowhere near 0% without it just as they are nowhere near 100% with it.

But chio linked to the strat thread late nov 2009 which indeed indicated what may be on the horizon based on strat patterns. Dave conceded this and as far as i am aware, is far more tolerant of the influence of the strat on trop patterns. Your final para is quite true.

[bobbydog]

Not really BD - sorry.

Naefs 12z quite different to 00z. In fi, uppers for london some 4c higher. Anomalys also dissimilar in both placement and intensiity. Naefs not noted for swings in output within a day so caution remains the watchword into week 2.

check the date of those charts then have a look through the archives. http://www.meteociel.fr/modeles/archives/archives.php?day=25&month=12&year=1990&hour=0&map=5&mode=0 not identical obviously but weather patterns were quite similar to now. point being, our current pattern does not discount some classic cold.... eventually.....

[Robbie Garrett]

Here comes the 18z, let's see how drunk it has got seeing as it's the holiday period

[cerneman]

As nobody has answered this post I will. The answer is yes. In his scepticism of the SSW theory, The Eye in the Sky pointed to December 2009 which brought freezing conditions and heavy snow to some places without any significant strat warming at all let alone a SSW.

I think the true position is that a SSW increases the chance of cold but they are nowhere near 0% without it just as they are nowhere near 100% with it.

Edit: sorry BA did answer this but hopefully my post is a more literal answer to the question.

Thanks Find subject interesting, Would it be right to say relativlely new sceince, Maybe sceince wrong word,

[Chris D]

SSW may be providing us with reasons for optimism, but do I recall correctly that the same signs indicated that the cold spell we had in first few days of February 2009 was set to get more severe into the second half?.

Certainly what actually happened was that it became increasingly mild and almost springlike

I'll take any period of cold/dry weather atm, its flippin' flooding out there! (although here obvs it's actually not that bad)

But anyhow, except for the far reaches of the distant future (in forecasting time) there is nothing of real note in any of the models, still. That is not to say that the background signals may become favourable in January.

Edited December 22, 2012 by Chris D

[Uncle_Barty]

With all due respect Frosty (and your posts are one's which I look out for when browsing this forum), I think you and many others are clutching at straws.

And as others have alluded to, this Strat Warming event may not have any effect (wintry wise) on Britain whatsoever at all.

I think it's best just to accept (for the forseeable) that anything remotely wintry is likely to be localised and on high ground, whether we like it or not. It's perhaps best to take the models at face value until something wintry appears and consolidates inside T96, fingers burnt and all that quite recently!

My sentiments, entirely.

Until there is a definite pattern change, cold fans are going to be chasing northerly topplers in FI.

My money is on such a change, but not until at least the end of the first week in Jan, and if the forecast strat warming comes off.

To that end, I would not expect to see much wholesale (i.e. over several runs and several models) change in the model output until the very turn of the year at the earliest.

[swfc]

50 mins without a post!!!!!Dont you wish a projected cold spell would show the consistency as the 18z is doing with this run lol.wheres all the shortwaves

[Bobby]

GFS 18z continues the zonal theme, no sign of ECM's mid-Atlantic ridge. More heavy rain however moving in to the South tomorrow night, another inch or more for flooded areas.

[Bobby]

Deckchairs and Ice cream anyone?

[Jason M]

Pub run out until day 11 now. Flat as a day 1 cricket pitch for an oval test match.

I defy anyone to say the 18z is not zonal. It's so awful that its funny. So much for northern blocking!

Still, we will have some shiny new runs in the morning and from this point the worst that could happen is that tomorrow's runs are as bad.

So in summary, mild, becoming milder still with lots of rain.

Jason

Nb let's see what the ensembles say.

Edited December 22, 2012 by Jason M

[nick sussex]

The UKMO fax charts continue to change frequently,for fear of causing some undue excitement in here IF and thats a big IF these do unbelievably verify it could get a little interesting Wednesday night into Thursday!

Low pressure moving east/se.

As this clears east some colder air heads south.

A chance there could be something wintry on the backedge more especially for northern areas.

Edited December 22, 2012 by nick sussex

[swfc]

Pub run out until day 11 now. Flat as a day 1 cricket pitch for an oval test match.

I defy anyone to say the 18z is not zonal. It's so awful that its funny. So much for northern blocking!

Still, we will have some shiny new runs in the morning and from this point the worst that could happen is that tomorrow's runs are as bad.

So in summary, mild, becoming milder still with lots of rain.

Jason

Nb let's see what the ensembles say.

keep the faith.the strat warming will save the day.7-10 jan!!!!

[Zakos]

Oh dear. looks like someone forgot to take there medication again.

Joking aside, there is a trend in FI for height rises to our east over Europe.

However, in the shorter term, there is an upgrade to the pattern. the lows are taking a slightly more southerly track, although nowhere near as much as on the ECM

No end to cool zonality in sight just yet. Hope now rests on stratospheric warming which is looking more and more likely to occur.

[Grimsby Snow Lover]

Pub run out until day 11 now. Flat as a day 1 cricket pitch for an oval test match.

I defy anyone to say the 18z is not zonal. It's so awful that its funny. So much for northern blocking!

Still, we will have some shiny new runs in the morning and from this point the worst that could happen is that tomorrow's runs are as bad.

So in summary, mild, becoming milder still with lots of rain.

Jason

Nb let's see what the ensembles say.

Sadly I have to agree with your post. It does however tie in with the metoffice's view of the models in their recent update. The colder weather, if any is only expected towards week 2 of January if the experts are to be believed. If thats the case then the GFS/ECM could churn out similar runs for a while yet.

[nick sussex]

Well if the GFS 18hrs verifies then NOAA yesterday had too much mulled wine when they talked of a more positive PNA!

In the shorter term there still seems to be disagreement with the low track into the UK Wednesday into Thursday, and this is why the fax charts are likely to chop and change a bit.

[reef]

The GFS 18z is a very poor run for anything cold, even the extremely brief cold incursion into Scotland on the 26th is completely gone on this run with the -5C 850hPa line just about hitting the Grampians compared to -10C or -12C before:

http://cdn.nwstatic..../h850t850eu.png

The outlook after that is then generally zonal with a mixture of very mild, dull, wet weather and average showery weather behind passing depressions.

Then into FI we get this, the dreaded Bartlett:

http://cdn.nwstatic....288/h500slp.png

It has been quite a few years since we've seen a proper one, but thats as fine an example as you'll get.

Fortunately its so far out chances are low at the moment, but its not a great pattern.

Edited December 22, 2012 by reef

[Jason M]

Ensembles out to day 9 and rock solid agreement that its full on turbo charged zonal all the way. The trend is for it to become progressively warmer over time as well as heights to our south continue to increase their influence. Absolutely no indication anyware of any northern blocking.

I've been concerned for several days that pressure was becoming ever more dominant to our south and tonight this process looks complete. Things cannot get worse from this point though as the pattern being shown is about as bad as it gets for cold. The only way from here is up.

Jason

Nb out to 240 now and to be fair there is greater divergence with some colder options starting to be shown.

[Neiller22]

The uk stinks for cold. Look !! We can look into fl all day long but the charts are crap! No sign of cold! The truth hurts!!! This winter stinks for the majority and personally I think it ain't going to get any better! Everything is fl and snd then it extends to fl again etc etch etc ! It's pxxs poor! And ain't getting better. All this about strat warming which I believe ain't making a button of difference!! Bout time we all woke up snd smled the coffee!! This country doesn't do cold weather!! It's rank. It's like chasing a needle in the hay stack !! I'm normally positive but iv come to the end of my tether! Somebody help me !!!

[Jason M]

Some pretty cold options in deep FI

Gut feeling tells me were in for a lengthy period of mild wet zonal weather which could last several weeks, but to be balanced there are a number of easterly options in the ensembles but out beyond day 10 largely.

Lets see what tomorrow brings :-)

[Panayiotis]

Fi now has constantly shown the Azores to move north into Europe, this puts us into SW winds bringing us mild and settled weather, but before this occurs there seems to be another 'phase' of heavy rain, which is the last thing the SW need!

So far this winter, the models have been disappointing, they show something nice with solid agreement for 2-4 days then slowly backtrack eg. The easterly and its looking more likely that next weeks cold spell isnt looking as good as it was a couple of days ago.

Edited December 23, 2012 by Panayiotis

[Cheshire Freeze]

Poor 18z....

Though a snippet of info.....Spoke to a guy in work today (customer). Anyway, he was discussing the flooding in the southwest and then went on to say this will continue over Christmas and into Jan. Now for the interesting bit......he said the highways agency have been given a heads up and told to stockpile grit for the middle of Jan as a potentially major cold spell may be on the cards.

No idea who he works for etc but seemed quite convincing that this is what he's been told and seems to tally with the potential warming event.

[dallas]

Well CC lets hope the models start to agree with him, as we could do a settled spell