Winter Forecast - 2011/2012

[leicsnow]

Late February under a 'cold high pressure system' can still deliver widespread very low maxima, extreme examples include 1956 and 1986 - under brilliant blue skies we saw intense cooling at night with mins widely below -10 degrees and maxima struggled to hit 0 degrees. It all depends on the synoptics. Even in 2005 when uppers were less favourable maxima did struggle to get much above 4-5 degrees. Northerlies can be very very cold indeed in late feb especially in the north even under blue skies and sunshine, temps often struggle to get above 2 degrees at best..

Snow does have a harder battle to stick to low ground by late feb esp in the south - but a deep cover can be much harder to shift.

It can happen like this in early March too.

[BLAST FROM THE PAST]

GP, just one quick question. You mention in detail how you study previous years with similar patterns.

Does any one year / winter stand out as being similar to what we might expect ??

I remember GP mentioned 1985 to me, can't remember if he was looking at winter 84/5 or 85/6. 85/6 would seem to fit better looking at the forecast and my memory of how that winter evolved into the Feb freeze up.

BFTP

[Catacol]

Re Feb and snow it very much depends where in the country you are.

by the last week in feb the sun gets pretty strong in the far south(i.e dorset), because of this a very very cold air mass is needed to stop it from melting over a few days.

In December though there probably isn't enough sun strength to actually melt fallen snow down here, hence when it does fall it tends to stay around longer, particularly so in Jan.

I've got a feeling futher north and definately in scotland the sun doesn't make much difference in Feb.

... and yet my memory of Feb 1996 in Dorchester was quite exceptional. Woke up to about a foot on snow in the Piddle valley, and all week Thomas Hardye school was at a virtual standstill as snow and ice stuck around for ages.

[AWD]

A very good and interesting forecast, one that I hope is correct as I do prefer snowfall after the new year! Doesn't disrupt the Christmas period when I tend to travel a lot!

Patience is the key for cold then, goes to show that a mild December doesn't mean winter is over, anything is possible in the new year!

Thankyou netweather

[A Winter's Tale]

Just seen the detailed forecast. It sounds brilliant and the detail and technical analysis is the best I've seen for any winter forecast this year.

Superb Work and I would love to see how mild or even chilly December is, the developments during January with the potential for cold during the month and how February turns out (It would be interesting to see what this February would turn out like and I would of course love to see something more solid in terms of cold).

With the potential for chilly December in Scotland and the likes of Weather Logistics and Mark Vogan looking at a cold second half, potentially cold January as stated by RJS and the interesting Feburary as published by Netweather, there seems to be some potential for something pretty cold and perhaps an average to slightly below average winter.

[January Snowstorm]

I remember GP mentioned 1985 to me, can't remember if he was looking at winter 84/5 or 85/6. 85/6 would seem to fit better looking at the forecast and my memory of how that winter evolved into the Feb freeze up.

BFTP

great thanks

[feb1991blizzard]

It can happen like this in early March too.

Yes. 1995 was a classic eg. Id almost gave up but then we had a dumping of about 5 inches (midlands) and the North hit -15 nightime minima over the snowfields.

[feb1991blizzard]

Just thought i would say that Stewart Rampling's forecast video is very well put together and what i like about it is that as long as you have very basic knowledge of weather you can interpret it but it is also fairly technical and detailed in parts too. I have people asking me what winter is going to do because they are worried about getting stuck in snow and i always give people an opinion with an elemant of the NW long range forecast incorporated, the only other people i would really trust would be the Met Office but they dont do seasonal forecasts anymore. Im not knocking other forecasters but they dont seem to put the detail of the drivers involved behind the forecasts they give, i would have a lot more respect for them even if they are wrong if they were more open about the methods they use rather than just saying things like 'low sunspot activity therefore southerly tracking jet all winter or 'Strong Nina therefore mild guaranteed'. Excellent work GP and i look forward to hearing updates.

[Tom Montalbano]

Well done Stewart/Paul. Very well prepared and an excellent presentation from Stewart.

Interesting to note how many times the mid-80s winters appeared in the analogues. The composites for Jan/Feb seem to produce a mix of 1985/86, with perhaps any cold shots coming a bit later than Jan 85 and perhaps a less extreme version of Feb 86, after all it would be pretty exceptional to a achieve that kind of CET for this coming Feb.

The analogues for pressure anomalies for Jan/Feb look very interesting with high pressure to our NE becoming influential as we go through Jan and becoming more dominant during Feb and with low pressure being forced further and further south. Certainly potential there for some battleground situations between mild Atlantic air and very cold Polar-Continental air. Here are a couple of charts from those winters I've mentioned above:

http://www.wetterzentrale.de/pics/archive/ra/1985/Rrea00119850117.gif

http://www.wetterzentrale.de/pics/archive/ra/1985/Rrea00119850209.gif

http://www.wetterzentrale.de/pics/archive/ra/1986/Rrea00119860215.gif

With the kind of pressure pattern Stewart envisages for the 2nd half of winter a chance that the much fabled "Channel Low", imo a term far too liberally used on this forum, could finally make an appearance. Obviously, i'm being far too specific about a feature that could possibly occur, in a very defined location, on the back of a forecast thats been produced for a few months down the line but for old times sake:

http://www.wetterzentrale.de/pics/archive/ra/1978/Rrea00119781231.gif

Slide rule precision to engulf the Midlands, south in heavy drifting snow. In my mind the Daddy of all "Channel Lows".

Anyway enough of old time sentiment!

Very best of luck with the forecast Stewart and as many have said already, much thanks for all the hard work you put into these LRFs.

O/T but it doesnt look like you foresee any problems for this years Boxing Day horse-racing programme from snow and frost, unlike last year of course, which was completely wiped out.

Regards,

Tom.

[Glacier Point]

Hi Stewart. Nice presentation.

I have placed a link to your presentation at the Belgium website weerwoord.be, the largest community of weather lovers in the Low Countries.

http://www.weerwoord...564&tid=1501564

Ben has a made a comment in this post, and I thought it might interested you.

http://www.weerwoord...099&tid=1501564

In Dutch

Ze gebruiken voor het maken van de composiet een (oude) heranalyse van NCEP. Daarbij relativeren ze niet de zwaktes van heranalyses in het algemeen en deze heranalyse in het bijzonder. Waarom worden er voor het composiet geen waarnemingen gebruikt?

Als je de twee belangrijkste heranalyses van de NCEP naast de waarnemingen zet (GISS), zie je dat de (nieuwere) 20th Century Reanalysis van NCEP een beter beeld geeft dan de heranalyse die Netweather gebruikt heeft. Het grootschalige patroon blijft hetzelfde, maar voor verwachtingen op landniveau zijn er toch her en der belangrijke verschillen (zie Spanje en IJsland bijvoorbeeld). In onze regio geeft de inschatting van NetWeather een normale winter (binnen 0,5°C van normaal over 1981-2010).

Translation in highlights

He wonders why you use the old NCEP reanalysis while there is a new one (20th Century Reanalysis). And the reason you didn't use temperatures (GISS)? In general terms the the temperature are the same but regional there are some differences.

Hi Sebastiaan, and thanks !

The 1981 - 2010 dataset has been used, mainly because I'm comfortable using this, particularly in relation to upper atmosphere data although there would appear to be minimal difference in H5 field anomalies. The temperature plots are to be used only as indicative, and are of less importance than the H5 plots - I wouldn't get hung up on the detail shown, it's more the trend that I would be interested in.

[ZONE 51]

Just would like to say excellent work GP!

A very interesting winter to come, hopefully more interest for mid Jan/Feb this time!

[Dorsetbred]

Update on the NW winter outlook due today?

[Paul]

There'll be an update of the CFS based long range forecast, but not the main winter outlook

[Glacier Point]

With the data in to 25/12/11, a good time to look to see how the forecast is going.

To remind ourselves, the forecast for December was for average or above average temperatures and a +AO regime.

The forecast pressure pattern based on composite analogues and observed mean sea level pressure anomalies alongside:

Temperature profile (forecast and observed) showing good verification on average or slightly above:

In terms of pressure patterns, very good, possibly a little flatter than the analogues, but very high correlation score and excellent on the overall temperature forecast for the UK. Bear in mind also that this forecast was essentially produced during late October.

Going forward, I've picked out some salient points from the forecast:

"There is some uncertainty as the timing of the ‘shift’ towards colder weather, however the most likely time is mid to late January and this will have a bearing on whether January is average, slightly warmer than average or colder than average overall."

"Putting these factors together suggests that the Arctic Oscillation is likely to be positive for the first month or six weeks of the winter, but with an increasing chance of warming of the stratosphere (potentially a rapid warming known as a Sudden Stratospheric Warming) leading to high pressure over the Arctic during late January and February and negative AO phase to finish."

"The analogues suggest a significant turnaround in air pressure over Europe with low pressure becoming dominant allowing much colder air to filter into Scandinavia (Arctic Oscillation becoming negative). This may be somewhat progressive given the upper atmosphere profile and I would favour a slower evolution and therefore high pressure more centred towards Scandinavia and the UK than shown here keeping things drier than normal."

"The analogue package suggests average or slightly below average temperatures which looks about right given other considerations."

Clearly the AO and this cold vortex event are a big deal and will not be overcome easily however this was expected, and the repeat warming waves in the stratosphere, allied to the idea that because this event started early, will end mid month (60 day rule), allied to the exceptionally good MJO analogues, all point towards a transition in both the NAO and the AO during the mid to late January period. So no reason to amend or alter a forecast (if it aint broke, don't fix it).

For guidance, analogue composites for temperature and sea level pressure forecast for January:

Edited December 29, 2011 by Glacier Point

[A Winter's Tale]

Thanks for the update GP, I do, however feel that you will need to review and revise by the middle of the month.

That could be the case if the models don't improve during the month coupled with little developments with the PV. BUT, I think eventually we'll end up in a better scenario and state of the stratosphere. Also, the good news is that there's still 45 days of winter left after mid January so there's still plenty of winter left.

Still, that was a bit confident of yourself to write off the in-depth research, analysis and knowledge and of GP and the fantastic work that he and the netweather team have done in past few months!

What's your forecast for the winter? What's your reasoning for it? What's your track record? What's your experience?

Well I've seen no winter forecast, no reasoning or theories, I'm unaware of any success in the past and I assume that you have the knowledge comparable to just the rest of us.

Leave it to the experts Ian Brown!!!

Edited January 2, 2012 by A Winter's Tale

[johnholmes]

AWT a touch over the top reply I think-all, including Ian, are entitled to their opinion. As to his experience maybe a polite pm before you posted might have been an idea.

[BLAST FROM THE PAST]

Thanks for the update GP, I do, however feel that you will need to review and revise by the middle of the month.

Ian, if December and Xmas had turned out as you had forecast, it didn't as it wasn't mild all the way with persistent SW'ly or no Bartlett scenario, and if the current outlook showed no signs of PV disruption etc then you may have a case. It hasn't and it would be appropriate for you to quantify your post and give a reason why. Just to remind you and folk that December and New year is going his way AND is very much going RJS way, it will be interesting to see where we head as they differ from their views on timings now, set up similar.

BFTP

[VillagePlank]

http://www.monbiot.com/2012/01/02/polar-opposites/

[mcweather]

Ian, if December and Xmas had turned out as you had forecast, it didn't as it wasn't mild all the way with persistent SW'ly or no Bartlett scenario, and if the current outlook showed no signs of PV disruption etc then you may have a case. It hasn't and it would be appropriate for you to quantify your post and give a reason why. Just to remind you and folk that December and New year is going his way AND is very much going RJS way, it will be interesting to see where we head as they differ from their views on timings now, set up similar.

BFTP

Hi BFTP

Tonights ECM seems to be picking up on the GP and RJS theme.

[BLAST FROM THE PAST]

Hi BFTP

Tonights ECM seems to be picking up on the GP and RJS theme.

Indeed it has and yesterday too, more to come over next few + days I suspect too from other models

BFTP

[Roger J Smith]

Liking the recent ECM output, feel that the current pattern may not even allow the 3-5 day mild spell shown, as there may be more energy rounding the top of the ridge and crashing southeast.

Not liking the continuous drumbeat of strawman style posts that take the form "X is wrong therefore anyone who mentions concepts that X mentions is wrong." Perhaps X (and Y) just haven't done their research very carefully -- much like the UK press who turn to them rather than more credible sources. Will cross-post this on the other strawman infested thread.

[A Winter's Tale]

Oh Dear, I read this on some other embarrising Winter Forum.

doylem wrote...Well there we have it a few comments creeping into this forum now about we might not have much chance of snowfall now.Well i could of told you that months ago.The NAO is set to flip back to positive in the coming days.So god only knows where peter o donnel got his info from.Or as they call him on netweather and two peter o donut..Not my words theres before you all jump on me.As ive been saying these past few evenings its now looking highly likely that the rest of winter will be dominated by the atlantic.Now i realise alot of people on here dont like that.But at the moment that is how things look more or less playing out.Doesnt matter how much you try and talk up this winter the facts are that we have had and are having a mild winter.And no matter how much people try and say its on its way it doesnt work like that.Alot of people on here have been saying its on its way since november.And has it happened no it hasnt.And will it happen well its looking highly unlikely.But thats how winters pan out sometimes.Maybe it will be cold next winter maybe it will be mild again.Who knows.But one thing is for sure at this moment in time winter doesnt look like making a sudden return.

http://www.dailymail.co.uk/debate/newsdebate/r/t-10229610/p-4/index.html

Peter O'Donut, what a daft thing to say and a lie. That person has obvioulsy not been reading this forum!

Any, RJS - what are your current thoughts on things and what particular factors is pivitol in your confidence of a colder period coming up this winter?

[leicsnow]

The Daily Mail forums are full of people 'sniping' and constantly expressing their preferences of the weather. They seem to rarely look at the state of the atmosphere and stuff.

To add to that it's hard to follow that forum, so I'm firmly in the belief that I'm better off here

[La Bise]

Lies and innacuracies on the Daily Mail....Well I never! What next, the Daily Express printing conspiracy theories about Diana's death...?

[Isolated Frost]

Lies and innacuracies on the Daily Mail....Well I never! What next, the Daily Express printing conspiracy theories about Diana's death...?

Haha!

Next you know the Daily Mail will be printing that immigrants give you cancer!

Fair to say it looks like GP bossed December to bits, and I have every ounce of confidence he will nail january as well. Enough substance technically for him to be on his way for another winter forecast success, but it's a long way away still...