The hunt for cold - Model discussion (late November)

[bluearmy]

8 minutes ago, johnholmes said:

Just a personal view but this is the more likely way to cold rather than looking east in my view. Not saying it will happen but the chances of deep cold, are more likely early in the season from a northerly outbreak initially.

Not sure about deep cold from a northerly John .... the most likely way we get sub -10c uppers to the majority of the uk is via a left over cold pool, trapped beneath a building scandi ridge and being advected west  ........ can’t see a northerly delivering deep cold in the first half of December.  Tbh, I wouldn’t like to have a stab at how any re amplification sets up re nw European surface conditions 

im pretty sure a train is coming .........just have no idea what platform it’s leaving from and how many carriages it will have by the time it gets here ! 

[feb1991blizzard]

4 minutes ago, bluearmy said:

Not sure about deep cold from a northerly John .... the most likely way we get sub -10c uppers to the majority of the uk is via a left over cold pool, trapped beneath a building scandi ridge and being advected west  ........ can’t see a northerly delivering deep cold in the first half of December.  Tbh, I wouldn’t like to have a stab at how any re amplification sets up re nw European surface conditions 

im pretty sure a train is coming .........just have no idea what platform it’s leaving from and how many carriages it will have by the time it gets here ! 

I would prefer a Northern rail timing with a Richard Branson First Class carriage quality!  -  in other words it takes ages to get here but at least its clean and comfortable when it does, we dont want an express timing but without carrying the actual goods like the one in your previous image thats just arrived.

[feb1991blizzard]

Lets hope it is a train 1.5km off the ground and it has -15c arriages!!

[Thundery wintry showers]

Historically this early in the season cold weather via northerlies has been a lot more common than from easterlies in late November and early December, although there have of course been exceptions like 18 November 1985, 20-23 November 1993 and 5-7 December 1995.  Sub -10C 850hPa air is somewhat rare from either north or east at this time of year although sub -8C is not that unusual.  This is partly because the continent and North Sea still have a fair amount of cooling to do, and partly because blocked easterly types with a persistent Scandinavian high are less likely to happen at this time of year.  The late Nov/early Dec 2010 instance saw the cold come from a mix of north and east winds but the easterly spell was brought about by a Greenland high ridging across to Scandinavia, and the coldest day in the CET area (28 November) arose after five days of northerlies, just as the easterly was starting to kick in.

In many recent years the warmth of the Arctic has meant that it was a struggle to get northerlies that were cold enough to bring lowland snowfall, but the Atlantic side of the Arctic has cooled down quite a lot this November and is currently relatively cold for recent years.  Of course there are regional differences - an easterly type is on average somewhat more reliable at bringing cold and potentially snowy weather to most of central and southern England, whereas over much of Scotland and north-east England it is the other way round - but taking the country as a whole the equation tends to be more in favour of northerlies early and late in the season with easterlies causing a higher percentage of significant cold snowy spells in January, February and early March.

Edited November 24, 2018 by Thundery wintry showers

[Met4Cast]

I really, really wish we had someone on here with access to MOGREPS, it’d be great to see what thats suggesting given the Met Offcie updates really haven’t backed down from the Atlantic being temporary.

I mean we can see that just looking at the models/ensembles we have access to but still! 

[feb1991blizzard]

4 minutes ago, Daniel Smith said:

I really, really wish we had someone on here with access to MOGREPS, it’d be great to see what thats suggesting given the Met Offcie updates really haven’t backed down from the Atlantic being temporary.

I mean we can see that just looking at the models/ensembles we have access to but still! 

Its probably the GLOSEA5 that they're going on, mid December is out of range for the MOGREPS.

[Derecho]

06z swingometers

 

A mild set for the start of December on the 06z but a fair contrast to the 00z so a lot to be resolved? The 00z had a lot of anticyclonic runs for the start of December only for the signal to be dropped this time. For December 6th plenty of runs on the cold side but nothing spectacular yet. Globally all the anomalous cold is being taken by Eurasia and Greenland. The odd cold foray for the UK on the back of passing lows. Some deep low pressure systems in the ens.

[Methuselah]

Here are the two GFS predictions for T+384:

As you can clearly see, the para has the Azores-Euro ridge in a somewhat 'less favourable' orientation, as far as the UK is concerned...?

[johnholmes]

1 hour ago, bluearmy said:

Not sure about deep cold from a northerly John .... the most likely way we get sub -10c uppers to the majority of the uk is via a left over cold pool, trapped beneath a building scandi ridge and being advected west  ........ can’t see a northerly delivering deep cold in the first half of December.  Tbh, I wouldn’t like to have a stab at how any re amplification sets up re nw European surface conditions 

im pretty sure a train is coming .........just have no idea what platform it’s leaving from and how many carriages it will have by the time it gets here ! 

Got to disagree with you b, my memory may be faulty but I am sure we have had -10 850 mb values from northerlies.

Had not noticed the post from TWS when I posted!

this link to see how that incredible spell of cold developed

http://www.wetterzentrale.de/reanalysis.php?uur=0000&var=1&nmaps=24&map=1&model=avn&jaar=2010&maand=11&dag=19

Edited November 24, 2018 by johnholmes
adding link to charts

[Methuselah]

4 minutes ago, johnholmes said:

Got to disagree with you b, my memory may be faulty but I am sure we have had -10 850 mb values from northerlies.

Had not noticed the post from TWS when I posted!

And when it does happen...  Bob's your auntie. To be PC!

[johnholmes]

3 minutes ago, Ed Stone said:

And when it does happen...  Bob's your auntie. To be PC!

I remember it well, snow on several separate days for Manchester Airport, great fun trying to get it right and keep the airport open!

[feb1991blizzard]

5 minutes ago, johnholmes said:

I remember it well, snow on several separate days for Manchester Airport, great fun trying to get it right and keep the airport open!

And i bet you succeeded, yet on Sunday Feb 1st 2009 after half an inch of snow - the runway closed - my how times have changed in this country - and not for the better either.

[johnholmes]

It has to be said that up to 14 days out the weather does not look, to me, to suggest any oset of deep cold. Beyond that is, as the saying goes, 'above my pay grade'!

Why do I say this=because of the upper air predictions showing nothing out to about 14 days that would allow any prolonged cold to set in.

links below

http://www.cpc.ncep.noaa.gov/products/predictions/610day/500mb.php

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

[Met4Cast]

7 minutes ago, johnholmes said:

It has to be said that up to 14 days out the weather does not look, to me, to suggest any oset of deep cold. Beyond that is, as the saying goes, 'above my pay grade'!

Why do I say this=because of the upper air predictions showing nothing out to about 14 days that would allow any prolonged cold to set in.

links below

http://www.cpc.ncep.noaa.gov/products/predictions/610day/500mb.php

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

I would tend to agree - Very unlikely to see deep cold in the next 15 days, stormy perhaps but drier towards day 15 as high pressure builds. 

Days 15-25 are where my interest currently rests

[Paul]

We've made a change to the way images can be embedded into posts, only uploaded images will show now - more info here:

If you have any questions about this, please ask in the thread linked above, not in here.

Edited November 24, 2018 by Paul

[Lynxus]

56 minutes ago, Ed Stone said:

And when it does happen...  Bob's your auntie. To be PC!

I was born in Dec 81.

 

Parents wont shut up about how cold it was, Nappies freezing, Drifts down the road, Kids having to walk up hill in 10ft snow both to and from school. Etc.

[Kentspur]

On 21/11/2018 at 20:13, markw2680 said:

I agree about being balanced but I just can’t help but think things could be looking sooo different by sat, I really struggle to see the block just blowing away. It was only a week ago the models was pretty much all looking awesome and now it’s quite the opposite, it only takes small changes for big improvements in our part of the world

Hi all,

I've not posted on here for a while. I thought I'd like to say thanks to all those knowledgeable posters on here for keeping us winter cold lovers educated. I love reading your daily insights into the synoptics.

While we're on the hunt for cold- all coldies must check out Gavin Partridges Seasonal model roundup for this winter 18/19.

Never have I seen so many models consistently showing very similar synoptic patterns with extensive High latitude blocking and prevalent Easterly winds! Only one model out of 13 shows a mild atlantic driven winter- (the new German model) 

Seems to be a consensus for a back loaded winter aswell going by the majority of the models. Very interesting times could be in store!

Heres hoping it's a cold snowy one.

John

[Mike Poole]

The 12s pretty uninspiring if I'm honest, this probably the best chart from the lot of them, GFS strat at T384, seemingly picking up on what yesterday's FV3 showed i.e. a potentially more significant warming down the line:

Otherwise GEM was awful, UKMO was still reasonably amplified at end of its short run, and GFS flirted with building some blocks before deciding it couldn't be ar*ed.

[bluearmy]

3 hours ago, Ed Stone said:

And when it does happen...  Bob's your auntie. To be PC!

Hate to be a pedant but that was no lower than -8c over Scotland ....... I was talking below -10 c and that v unusual from a proper northerly in December .......

[northwestsnow]

2 minutes ago, bluearmy said:

Hate to be a pedant but that was no lower than -8c over Scotland ....... I was talking below -10 c and that v unusual from a proper northerly in December .......

LOL Blue.

GFS turning on the zonal turbo tonight, ukmo looks more amplified out to the east so i'll not be losing any sleep over GFS..

 

[syed2878]

Hi guys although models are not showing much wintery outputs at the moment I think it's mid winter onward when the fun and games will start looking at the seasonal models on gavs weather vids. I posted a cuppal of these recently so I will share this 1 from gavs weather vids and it's last seasonal models update before the winter kicks in and I must say it's quite exciting from jan onward. 

 

[Decemberof2010]

Pert 10 says cheer up coldies I’ll be here in a couple of weeks

[Paul]

Please head over to the winter thread to discuss lrf's and the like - Chris Fawkes one is already being discussed over there.

 

[jules216]

While waiting what ECMWF brings I was looking where the block meets Atlantic energy next Monday/Tuesday. It will be right over my home region in Slovakia. GFS has around 12C spread on its ensemble suite with just 3 day to go. Uncertainty at its best  

[Seasonality]

35 minutes ago, jules216 said:

While waiting what ECMWF brings I was looking where the block meets Atlantic energy next Monday/Tuesday. It will be right over my home region in Slovakia. GFS has around 12C spread on its ensemble suite with just 3 day to go. Uncertainty at its best  

I know!  For Warsaw on the 1st of December the spread of 850hpa temps on the ensembles is from -15 to +6!