Winter Model Discussion 18Z 19/1/13 onwards.

[Weathizard]

The thing I don't understand is, I know the SSW was probably a direct help for us during this current cold spell, people said the main effects are felt 14-28 days after, now the SSW occured on the 6th January, yet the models don't really show a sign in the 14-28 day range of any real donwelling into the trophosphere. Yes we have a split vortex to a point with an Arctic high(which we actually have had for a lot of this winter) but given how weak the vortex was even before the SSW occured it surprises me we are not seeing bigger effects. To be quite honest the models and ens mean are showing the exact opposite of what you expect with vortex reforming to the north of us and high pressure rising over the Azores/Iberia. Given that people say the effects can all of a sudden appear in the models is it wise to say 'go away for a week' or 'no more cold until after at least first week of Feb'

[WhiteFox]

Have to agree with TEITS and Steve M - the medium term pattern is very poor as far as cold is concerned. Yep, we know things can change pretty quickly but as it stands right now, no return to cold till Feb 10th at the earliest.

This is true. For cold weather, the forecast pattern after the weekend is as bad as it gets. However, am I only one who thinks that the idea of a euro high metling the snow is far preferable to a big dumping of snow which then melts rapidly in the ensuing heavy rain and causes further flooding problems? Whilst a fan of snow, I prefer the sort that sticks around; the last thing we need is large amounts of snow followed by a rapid thaw.

Anyway, as regards the winter so far, I dare say that had the mild period of 1988 - 2008 not happened, this would be classed as an average winter. Severe months are rare (which is why they are severe) and I'm thinking that SSW is a requirement to deliver what we would class as "normal" winter synoptics. A discussion for another thread, but how much research has been done into SSW events and their effects over winters past? Did we have a lack of SSW during the period 1988 - 2008 which led to the jet tracking further north on average?

[SMU]

Heres an interesting one--since the warming event the AO index has struggled to get to -2 on the scale..

Interesting- but hardly a huge hemispheric breakdown--- lucky the the wedge of high pressure had landed in our corner!

S

Edited January 22, 2013 by Steve Murr

[BLAST FROM THE PAST]

I think this is a key statement. The point is that the Canadian vortex will not be "gone". It is under attack and is set to empty into the atlantic giving us our breakdown... but then ensemble forecasts now have it reforming somewhat, and linking with the siberian half that shows no sign yet of dropping westwards towards us as long term forecasters believed it would.

Steve is right - if we get reformation of vortex low pressure to the north and a consequent rise of pressure to the south then this is a pattern that will probably lock in for a fortnight and by then winter is on the ebb. That is not to say that a cold spell in mid Feb is out of the question... and your stats on Feb snow are correct... but it is a long way from the wintry spell that forecasters predicted.

So far long term forecasting for this season has not done so well as previous winters. December went awry and with the breakdown on its way we will have had 1 week of coldish (it actually hasnt been that cold) weather with some snow but nothing especially remarkable on a national scale.

Snow is getting all the headlines in the press at the moment, but as winters go I think thusfar it has been very ordinary.

Just pick up the bit in bold, it has been very cold, 0c or even +1c maxima is very cold no matter what 30 yr mean one uses. Also in Redhill we hit double digit minus minima last night and in my books that's mighty cold

Yes it hasn't been a spell to go into the history book and this is where I think folk are getting caught up. It seems folks are always seeking the cold spell that goes down in folklore and if it doesn't happen then its a poor cold spell. Reality is its been v cold with temps WELL BELOW normal.

Jan CET is 4.2c, which is achieved by temps thast fluctuate to double figures to sub zero temps and clearly shows that the UK does not get regular month long freezes or regular super freezes.

Also location can and does make a huge difference. Feb 1986 was an immense month. -1.1c CET for the month. In Swansea/S Wales we were lucky and it was a mega month, one I'll never forget. This was because we had a good dumping of snow at the beginning and it lay on the ground for the month with bitter east winds. We didn't get much snow after but because we had a good dumping it didin't matter. Other areas didn't get the dumping and had a very dry month, which although super cold it isn't remembered because it was dry.

For me what makes a good winter is the cold, but it is clear that for many if not most...its snow amounts.

Now as regards to the LRFs, yes indeed some hold onto every post, nothing wrong with that but be prepared to be let down...because you will be at some point

BFTP

Edited January 22, 2013 by BLAST FROM THE PAST

[No Balls Like Snow Balls]

I don't understand why a lot of you are ranting and raving about no cold showing in the models and hang off every word of the so called experts - The same so called expert that ranted about no cold weather in the foreseeable about 3 days before this current cold spell appeared. They wasn't right last time so what makes them right this time???

[BLAST FROM THE PAST]

GP owns 1, ask him

But hasn't used it yet then?

BFTP

[swfc]

Such fine lines are drawn with the synoptics in the uk and i guess its what makes it what it is.Looking at that huge arctic high and wishing it would slip south west?Im not buying into any cold spell arriving on any set timescale simply because forecasting is so complicated over a 48 hr period so id fall into the sm camp on this one.This current cold spell as been sustained on very poor blocking so that has learnt me something.As feb approaches there will always be a chance of a cold outbreak but that would apply most years ssw or not i guess

[UV-RAY]

Why is it when comments on what the models are showing are looked upon in disdain, if the models only show mild then that's all we can comment on. It's been a sorry episode in the model thread this winter, where good posters get lambasted for daring to suggest the outlook is poor.

Anyway, rant over and we have model consensus of a much milder pattern setting in from this weekend, this lasting at least 7-10 days out. All talk of Greenland heights and cold reloads are pie in the sky at this moment in time, off course that's not to say this time next week we could be looking at charts showing such delights.

Edited January 22, 2013 by Sceptical Inquirer

[TEITS]

Yes we have a split vortex to a point with an Arctic high(which we actually have had for a lot of this winter) but given how weak the vortex was even before the SSW occured it surprises me we are not seeing bigger effects. To be quite honest the models and ens mean are showing the exact opposite of what you expect with vortex reforming to the north of us and high pressure rising over the Azores/Iberia. Given that people say the effects can all of a sudden appear in the models is it wise to say 'go away for a week' or 'no more cold until after at least first week of Feb'

Im surprised at the output to be honest but you have to remember the Strat is only one piece of the jigsaw.

When I first joined this forum I started looking at all kinds of different forecasts that used various different methods but these days I just prefer to stick with what the models are showing. I feel Steve M is the same as me because I remember SM used to post very long, technical winter forecasts but has since given up doing this. The reason for this is like me Steve isn't interested in what LRF are saying and prefers to see the reality in the actual model output. We also share the same view that producing an accurate long range winter forecast is an impossible task for the UK. My point is it doesn't matter what anyone else is saying if this isn't being shown in the model output.

One of the most disappointing aspects of the winter so far isn't just the lack of a GH but the NAO. Look at these actual recorded SLP at Lisbon, Reyjavic and you will see the NAO has been mainly neutral and at times positive with just a few occasions of being slightly negative.

The cause of this is the persistant HP to our S and the lack of blocking towards Greenland.

P.S Sorry Steve if I made any wrong assumptions.

[Matty M]

A real problem i find with winter in the UK and the models. They are generally very reliable in predicting mild weather, fore example the outlook for the weekend and beyond was reall nailed by the GFS 5 days ago and by the rest 3-4 days ago. While forecasts of cold weather usually downgrade or are extremely unreliable even 4 days out.

Is there an actual reason for this or is it just my flawed perception?

[TEITS]

Final post for the morning.

To all those who are complaining about mine & Steve M negative posts this morning. Please could you post a chart from any model that suggests a return to cold between +144 to +240. Also try and find a chart that suggests any form of blocking to our N in the same time period.

Good luck!!

[Methuselah]

Now as regards to the LRFs, yes indeed some hold onto every post, nothing wrong with that but be prepared to be let down...because you will be at some point

BFTP

Some do, yes...

[BLAST FROM THE PAST]

A real problem i find with winter in the UK and the models. They are generally very reliable in predicting mild weather, fore example the outlook for the weekend and beyond was reall nailed by the GFS 5 days ago and by the rest 3-4 days ago. While forecasts of cold weather usually downgrade or are extremely unreliable even 4 days out.

Is there an actual reason for this or is it just my flawed perception?

We are only Tuesday, so nothing is nailed. it looks favourite for sure model wise but I do not trust model's reliability at all currently. No I'm not advocating a raging Easterly this weekend with awesome northern blocking, but I reserve judgement just now on how we shift our pattern.

TEITS, I'm not going to bother and try, models have been rubbish and probably still are beyong t96 this winter.

BFTP

Edited January 22, 2013 by BLAST FROM THE PAST

[No Balls Like Snow Balls]

Latest from Twitter

26 out of the 51 ensemble members signal a more anticyclonic influence by the 6th of Feb, with a far 'quieter' Atlantic.

Subtle signs of a change within the ECM ensembles beyond 4th/5th with the Atlantic flow being disrupted by higher pressure.

Bet there will still be plenty of winter is over posts today.

Edited January 22, 2013 by No balls like Snow Balls

[swfc]

A real problem i find with winter in the UK and the models. They are generally very reliable in predicting mild weather, fore example the outlook for the weekend and beyond was reall nailed by the GFS 5 days ago and by the rest 3-4 days ago. While forecasts of cold weather usually downgrade or are extremely unreliable even 4 days out.

Is there an actual reason for this or is it just my flawed perception?

The general pattern in our parts is for a west to east movement of weather systems so i guess it is less flawed and confused"lol"than in a blocked or projected cold spell.the 06z at 144 hrs is a thing of horror from a cold spell perspective

[Troubleatmill]

A real problem i find with winter in the UK and the models. They are generally very reliable in predicting mild weather, fore example the outlook for the weekend and beyond was reall nailed by the GFS 5 days ago and by the rest 3-4 days ago. While forecasts of cold weather usually downgrade or are extremely unreliable even 4 days out.

Is there an actual reason for this or is it just my flawed perception?

Yep strange isnt it Matty, i am only guessing that its because zonal is easy to forecast, actual details arent pinned down anymore than in a cold spell but its a pattern that does by default keep going and once in it just feeds its self off the atlantic, which is the biggest engine there is,

Looking at this chart its reminded me how unwindy its been this winter (and autumn) no storms hitting our shores that i can recall??

Edited January 22, 2013 by Nick JB

[TEITS]

Latest from Twitter

26 out of the 51 ensemble members signal a more anticyclonic influence by the 6th of Feb, with a far 'quieter' Atlantic.

Subtle signs of a change within the ECM ensembles beyond 4th/5th with the Atlantic flow being disrupted by higher pressure.

Bet there will still be plenty of winter is over posts today.

Who has said winter is over this morning?

All im saying is the model output between +144 to +240 is rubbish especially the ensemble means. This doesn't mean im ruling out some of the excellent recent GFS runs that have shown a GH at +384. However from experience I rarely get excited at charts at +384 and due to the timeframe it isn't worth discussing until this gets much closer.

.

TEITS, I'm not going to bother and try, models have been rubbish and probably still are beyong t96 this winter.

BFTP

Come on Fred the signal is so strong for a return to mild SW,lys at +144. I would even say I have a greater chance of winning the Lotto than a sudden switch in the output at +144.

Edited January 22, 2013 by THE EYE IN THE SKY

[No Balls Like Snow Balls]

Final post for the morning.

To all those who are complaining about mine & Steve M negative posts this morning. Please could you post a chart from any model that suggests a return to cold between +144 to +240. Also try and find a chart that suggests any form of blocking to our N in the same time period.

Good luck!!

There are no charts. But why do you now take them as gospel? - very bizarre.

Edited January 22, 2013 by No balls like Snow Balls

[swfc]

Latest from Twitter

26 out of the 51 ensemble members signal a more anticyclonic influence by the 6th of Feb, with a far 'quieter' Atlantic.

Subtle signs of a change within the ECM ensembles beyond 4th/5th with the Atlantic flow being disrupted by higher pressure.Thats a tweet regarding the ecm ensembles not a meto update or weather forecast?I cant see any "winter is over forecasts"but looking at the 06z 144 hrs onwards nothing wintry or resembling cold there.Febuary may throw the uk a cold spell but maybe not

Bet there will still be plenty of winter is over posts today.

[No Balls Like Snow Balls]

Yes I know. What has the meteo update or a forecast go to do with it?. I was just showing the other side to the negativity.

[SMU]

Latest from Twitter

26 out of the 51 ensemble members signal a more anticyclonic influence by the 6th of Feb, with a far 'quieter' Atlantic.

Subtle signs of a change within the ECM ensembles beyond 4th/5th with the Atlantic flow being disrupted by higher pressure.

Bet there will still be plenty of winter is over posts today.

26/51....

so then an exact 50% split-

you may have also say that 25 dont...... so based on that info there is no clear pattern...

S

[No Balls Like Snow Balls]

26/51....

so then an exact 50% split-

you may have also say that 25 dont...... so based on that info there is no clear pattern...

S

Exactly. So no real need for any negativity.

[swfc]

From 144 hrs out those charts really dont get much worse from the 06z.Call it fi if you like but its looking like the pv is really ramping up and that high to the south looks strong.

[bluearmy]

there appears to be a lot of 'depressing' posting this morning. i guess anything next week that isnt freezing and snowfilled is going to be a let down ! i still see heights remaining fairly high the further se you are in the uk. just how 'warm' any high is going to be seems open to question. no appetite from the ecm ens mean to get much above 2c 850's. i would wait for the models to settle down re next week as to where they place the flow and euro high. could be sceuro, could be east atlantic (unlikely), could be bartlett, could be more belgium/ne france/se uk. different placements will lead to different surface conditions here. what is clear is that if the modelling is reasonably accurate (and there is no reason to suppose it isnt), we have at least a week and probably two without any deep cold. maybe thats what is depressing some folk. seems like standard winter fayre. no reason to think that a retrogression into the mid atlantic and possibly further north wont follow this period. at that range we are relying more on telecons and thats what seems to be the current thinking.

[TEITS]

Exactly. So no real need for any negativity.

Yes but we are talking well into FI i.e +384.

If we are relying on discussing charts at +384 then this just illustrates how poor the output is prior to this!