Winter Model Discussion - The Hunt For Cold -12z 14/12/12

[SMU]

Morning-

Lets hope this is the low point of the winter-

Awful outputs, no blocking- over 60N - vortex whilst not over the whole polar region - still all together & not split.

The snow risk for that NE flow isnt widespread- just local to NE scotland

And to top it off a high probability of a mild XMAS.

S

[UV-RAY]

A few tweets from Matt Hugo, lets hope the seasonal models are woefully wrong! Some dreadful outputs this morning and the less said about them the better. The EC32 updates today so lets hope for some good news later.

Matthew Hugo

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MattHugo81

To finalise the seasonal models for this year, the EUROSIP model has updated and shows a zonal picture for the rest of the winter.

Matthew Hugo

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@

MattHugo81

Despite the other 'signs and signals' the seasonal models have been steadfast in their agreement/consistency for an unsettled/zonal winter.

Indeed, with the EUROSIP being the last model to come on board the zonal train, then you have to say that they all can't be wrong and the signal for a mild zonal winter must be pretty strong. What did those teleconnections say again?

Edited December 17, 2012 by Seven of Nine

[MattH]

Are these not the same models that were showing blocked pattern and an Easterly last week. Pinch of salt.

Nope that is the ECM32 day model, which indeed, like the other deterministic models quickly changed a week or two ago, but that's the way it goes. The seasonal models are different, but they are just that 'models' and can be wrong which only time will tell.

M.

NB: As an additional after using the EC32 day and the variety of information available from it operationally for over a year it has been correct far more than it has been incorrect despite failing miserably of late.

[Froze were the Days]

Are these not the same models that were showing blocked pattern and an Easterly last week. Pinch of salt.

Yes I think they were, looks like the CFS v2 model might not be too far out, saying that looked at it a bit earlier and showed a brief easterly in the New Year. Overall everything looks a bit disappointing.

[Snowman31]

I've got feeling its just not going to happen this winter, everything that can go wrong seems to be happening. There is not much hope for december IMHO. I don't even know if I want the block to the E to stay or go, but every scenario on the models seems to result in us missing out, except perhaps in +360. I think we should hope that January will deliver something or this might be the worst winter in terms of hope and potential only to be let down.

Edited December 17, 2012 by Snowman31

[bradymk]

Unfortunately it looks like my fear of the high to the east is becoming more of a hinderence than anything else now. I dont think it is going to help us now (but i will give it until after the 12z's) and will delay any northerly outbreak which is going to be preceded by Sw lys anyway. However i still think a northerly outbreak is likely but delayed by 2 or 3 days. Will it be more transient than anything else though, hard to tell yet.

Edited December 17, 2012 by bradythemole

[Froze were the Days]

Obviously I was wrong!

[Theresnoway]

Indeed, with the EUROSIP being the last model to come on board the zonal train, then you have to say that they all can't be wrong and the signal for a mild zonal winter must be pretty strong. What did those teleconnections say again?

Whilst the signal might be "pretty strong", it does not mean it is right. If the medium range forecast can change at the drop of a hat, then I would not give too much weight to any long range forecast. I think some people fall into the trap of thinking well the models show it, so it must be right. How many times have we seen this not to be the case?

In fact I would go as far to say, I feel more comfortable with them showing warm. Because when a cold outlook is forecasted at long range, it rarely seems to materialise.

I would use the models and trends as guidance, not matter of fact! It may very well, and probably will change and change again.

Plus surely the teleconnection forecasts are just a set of results from a long range model, so what means that these forecasts are going to come to fruition?

Edited December 17, 2012 by Theresnoway

[Troubleatmill]

CFS is a belter for a cold easterly to cheer everyone up, way off out in la la but best i could find lol!

http://www.meteociel...&carte=0&run=10

Edited December 17, 2012 by Nick JB

[chris55]

Iberian ridge is not a dead cert yet!! Push things south a little more and an easterly is still possible. Wonder what the 12zs will bring.

http://www.wetterzentrale.de/pics/Recm1201.gif

http://www.wetterzentrale.de/pics/Recm1441.gif

[PMPhotography]

Nope that is the ECM32 day model, which indeed, like the other deterministic models quickly changed a week or two ago, but that's the way it goes. The seasonal models are different, but they are just that 'models' and can be wrong which only time will tell.

M.

NB: As an additional after using the EC32 day and the variety of information available from it operationally for over a year it has been correct far more than it has been incorrect despite failing miserably of late.

Ooops. Fair play.

What are the verification stats like for these models? If short/ Medium term models have recently struggled surely confidence in long range models would be lower? I'd be curious as to what they forecast in situations against the norm such as 2010?

Is the Glosea4 similar also? I think i saw that was also showing zonal.

[IDO]

Whilst the signal might be "pretty strong", it does not mean it is right. If the medium range forecast can change at the drop of a hat, then I would not give too much weight to any long range forecast. I think some people fall into the trap of thinking well the models show it, so it must be right. How many times have we seen this not to be the case?

In fact I would go as far to say, I feel more comfortable with them showing warm. Because when a cold outlook is forecasted at long range, it rarely seems to materialise.

I would use the models and trends as guidance, not matter of fact! It may very well, and probably will change and change again.

Plus surely the teleconnection forecasts are just a set of results from a long range model, so what means that these forecasts are going to come to fruition?

We have been in favorable blocking for sometime now and all we are seeing is cyclonic westerlies trending to a zonal or UK hp cell Synoptics. Once the blocking goes then we are likely to default to one of these patterns. Without further stratospheric events the UK will possibly stuck in one or both of these scenarios. Of course there will be the odd transitional colder flow but otherwise a poor situation for cold. The strat. Warming in January is no done deal so overall things remain downbeat for the UK winter. I remember last year members were saying don't write off the winter there is still two months left, we all know what happened....

Edited December 17, 2012 by i'm dreaming of...

[Liam J]

I'm afraid the weather takes no pity on us, what will be will be. Even if we end up writing off one month of winter that still leaves us with 2 whole months to play with. Can we turn it around?! If things carry on in the same vein then you'd really have to question just how valid all the background and teleconnection signals are for our small part of the world.

Going to stock up on extra alcohol to ease the pain of what looks like it could be a mild, wet & windy Christmas 2012!

Edited December 17, 2012 by Liam J

[Frosty.]

Going to stock up on extra alcohol to ease the pain of what looks it like could be a mild, wet & windy Christmas 2012!

Good idea, maybe the models will look better through beer goggles

[TEITS]

The overall output in the medium range might be disappointing but before we call these runs poor lets spare a thought for those living in E Scotland because you would be delighted with todays output in the short term.

A cold E/NE,ly into Scotland (Maybe far N of N England) is very much on today with the risk of snow. However still some room for improvement as the cold E/NE,ly might be further S. Have a look at the ensembles for my location.

http://cdn.nwstatic.co.uk/ensimages/ens.20121217/00/t850Cambridgeshire.png

I haven't looked at each ensemble member but im assuming some members take the SW much further S resulting in a cold E/NE,ly even for my location. Also look at the SW on the 0Z GFS at +72 underneath the main LP.

Potential for this to develop and track S helping to pull in the colder E/NE,ly flow.

[Gibby]

Good morning. Here is the report on the 00z's from GFS, UKMO, GEM and ECM for today Monday December 17th 2012.

All models show a Westerly flow over the Southern half of the UK with a mix of sunshine and showers. Northern areas see slacker winds as a shallow Low pressure drifts East across the area during the day. Tomorrow sees a weak ridge across the UK before a new Low in mid Atlantic winds up and pushes troughs into the SW of the UK and moves them slowly NE to other areas. In the second half of the week it's a case of how these troughs interact over the UK against a cold pressure block to the NE. The net result would probably be mild and unsettled conditions in the SW half of the UK with rain or showers continuing while NE areas see rather colder weather with the risk of ome snowfall on higher ground later in the week.

GFS then starts the weekend with the pattern maintained with further rain mocing into the SW and hitting the buffers in the NE as the cold block to the NE holds on a while longer with further rain or snow. In the final days before Christmas the block collapses and with deep Low pressure up to the North pre Christmas Eve milder and unsettled conditions extend to all areas with rain at times. The Christmas period is shown to be a green one with the traditional Low to the North and High to the South pattern with a broad Westerly flow over the UK with rain at times, most persistent in the North and West. The remainder of the period up to and including the New Year shows little change in theis pattern with winds mainly Westerly bringing rain bearing troughs East periodically across the UK in relatively mild conditions for all.

The GFS Ensembles show a very poor chance of snow at Christmas with the entire run showing a relatively mild period with plenty of rain around for all. There is a colder blip at the end of this week for more Northern and Eastern areas briefly before the block to the East finally collapses and allows the Atlantic to affect all areas between Christmas and into the New Year. There is a lot of spread between the members in the second half of the run with some colder options shown, none of which are particularly cold.

The Jet Stream shows a West to East flow crossing over the Atlantic to Europe. In the following period the flow takes a more sine wave pattern ridging and troughing within the vicinity of the UK.

UKMO for midnight on Sunday shows Low pressure several hundred miles West of Scotland with a trough crossing NE over Southern and Western areas bringing yet more rain and strong winds in rather mild air. Northern and Eastern areas may still be rather colder ahead of the rain area down to the SW.

GEM shows a very disturbed latter end to its run as Low pressure over the UK move away East with rain giving way to a colder snap with wintry showers briefly over Northern and Eastern UK over Christmas Day before a quick return to Westerly winds and milder air after Christmas.

ECM shows a chillier weekend for many away from the SW where troughs continue to bring rain at times. Towards Christmas a large Atlantic depression pushes against the block to the East, strengthening winds and pulling troughs North and East over all areas, making for a wet and windy Christmas and a showery WNW flow to end the run.

In Summary it looks like this week will see changeable conditions with a rather colder interlude for Northern and far Eastern areas of the UK while the South and West see rain at times with some mild air entrained at times. The colder air loses the battle at the weekend as the Atlantic Low pressure pushes against the European cold block, collapsing it and opening the door to allow the mild and wet conditions in the SW to spread NE to all areas in time for Christmas with a green rather than white Christmas virtually guaranteed from the operational output described here today. The period following Christmas remains unsettled and relatively mild with rain at times.

[BLAST FROM THE PAST]

Morning-

Lets hope this is the low point of the winter-

Awful outputs, no blocking- over 60N - vortex whilst not over the whole polar region - still all together & not split.

The snow risk for that NE flow isnt widespread- just local to NE scotland

And to top it off a high probability of a mild XMAS.

S

I doubt it Steve, yes a disturbed pattern for Xmas with heights to our sout prevalent and deep LPs in our locale. Possible short term northerly New Year early Jan but disturbed pattern IMO likely through large portion of Jan. The heights to our NW show no sign of developing at all in neartime, indeed not even mid range. My view is for time being lets get used to it. Christmas Day, Boxing Day could be quite stormy for some. ALL the models have to be woefully wrong for any strong blocking to our NW to develop in next week or two.

BFTP

[wolvesfan]

Morning all,

Model output not good at the moment for any cold longevity,long term it seems the Azores high will have the greatest bearing on the UK weather with most models showing it taking control.the Icelandic low becoming more prominent delivering a classic +NAO.we all know what follows.

It seems we may need to see something quick from the strat before the zonal flow locks in.

[Frosty.]

The good thing about a stormy zonal pattern is we should at least have some cold incursions with shortlived snow chances and frosts between the milder, wet and windy spells. A fast moving pattern with occasional amplification is better than endless swly mush.

[Polar Maritime]

Just to lift some spirits.... at least we are only 17 days into winter ! December was not forecast by GP (out of the 3 winter months) to be anything noteworthy, Average or just below was the main theme, and things seem to be going to plan so far.

And if thing's continue as they are with strat warmings modeled for around Christmas, then Jan/Feb could very well be on our side, with below/ or well below temp's as forecast by GP.

Jan/Feb can deliver extremely cold condition's for the UK, as we have seen in the past. Also i would not write off some good PM shot's around Christmas, the models have been flip/flopping for weeks now and are very unpredictable.

[Ian Brown]

Well we see from the models how the block to the East tries to hang on in the face of the jet and the rising pressure over Iberia before final defeat around T168.

We then look to be in a zonal reset with a progressive flow across the North Atlantic and the organisation of the PV to the North West, certainly if we get to the position shown by the GFS and ECM by day 10, it's a long road back to any blocking.

[Matty M]

ECM postage stamps indicate game still on. This is mighty tense. The ECM OP was a MILD SOL!

[Snowman31]

Everything seems more west already on the 6 run. I don't know if that is good or bad anymore to be honest.

[TEITS]

Everything seems more west already on the 6 run. I don't know if that is good or bad anymore to be honest.

Now its really all about the track of the SW's.

Ideally you want these as far S as possible. This also includes the other SW that is S of the main LP in the Atlantic. The further S the more likely the colder E,lys will affect those further S.

[Continental Climate]

Just to lift some spirits.... at least we are only 17 days into winter ! December was not forecast by GP (out of the 3 winter months) to be anything noteworthy, Average or just below was the main theme, and things seem to be going to plan so far.

And if thing's continue as they are with strat warmings modeled for around Christmas, then Jan/Feb could very well be on our side, with below/ or well below temp's as forecast by GP.

Jan/Feb can deliver extremely cold condition's for the UK, as we have seen in the past. Also i would not write off some good PM shot's around Christmas, the models have been flip/flopping for weeks now and are very unpredictable.

Not sure about that mate maybe listen to the forecast again im sure he said some cold around the start of the month and definitely by the middle/end of the month!! Unlikely to get any cold by months end apart from transitory topplers and the such!!