Model Output Discussion - cold spell to end Autumn

[Met4Cast]

Well..

GFS does like to overblow low pressure systems to correcting South as per 18z is expected/weaker low when it does actually arrive. The low will be crossing the UK on Wednesday, that's pretty much nailed. What isn't nailed is the track/intensity. 

GFS/UKMO broadly in agreement with a shallower low crossing further South. ECM has the low deeper and thus further North, but it's hard to see where the low crosses because of the 24hr time jumps.

I'd punt at the low crossing Eastwards somewhere along the M4/South-Midlands at a push for Northern extent, that puts the snow risk pretty much everywhere South of N England. 

[igloo]

and it just gets better the final frames we have a greenland HP and the siberian HP marching west at the same time mad run

[MKN]

19 minutes ago, J-Man said:

Just 132 hrs from now.

 

 

Given the type of scenario we are dealing with this wouldnt be guarenteed at +48 let alone +132.

[SMU]

24 minutes ago, ShortWaveHell said:

Iv worked out how you’re so knowledgeable , you’re from the future , your clock is nearly at 11pm us mere mortals are 15 mins behind. 

Ha - ive been in the delorean & gone forward 15 mins

lets see what the mean & control looks like-

I think Dannys estimate is correct -M4 for track seems good to me ...  possible blizzards for some as the Northerlies undercut the PPN

[J-Man]

Just now, MKN said:

Given the type of scenario we are dealing with this wouldnt be guarenteed at +48 let alone +132.

I think the gfs has been quite reasonable over past 5 weeks, yes things drop in the drop out then back in again but so far this autumn its generally been on the ball with the patterns.  Lets hope it continues over coming month.

[markw2680]

15 minutes ago, northwestsnow said:

Well meto still talking of wind and rain and wintry showers following behind.

After seeing 18z GFS i would be extremely dis-satisfied with wintry showers...

Pretty please ECM..stop being a bugger your causing my hair to go grey..

Don’t no about grey mine is falling out after going on to many rollercoasters. Sorry mods couldn’t resist

[Ice Day]

Just a few images of what could be coming for next week before bed.  Sweet dreams!!!

   

Edited December 1, 2017 by Ice Day

[SMU]

Mean & control all shifted south inline with op @114 Also CAA coming south towards the UK

we are now just at T120 showing near perfect allignment for a storm..

Edited December 1, 2017 by Steve Murr

[East_England_Stormchaser91]

Wonder if this will be rivalled, the blizzard of 30 December 1962! 

Also a deep concern that many of the most recent new drivers have never experienced driving in snow at all, let alone drifts of it! 

Edited December 1, 2017 by East_England_Stormchaser91

[northwestsnow]

7 minutes ago, Steve Murr said:

Mean & control all shifted south inline with op @114 Also CAA coming south towards the UK

we now just the day 5 mean showing near perfect allignment for a storm..

 

 

7 minutes ago, Steve Murr said:

Mean & control all shifted south inline with op @114 Also CAA coming south towards the UK

we now just the day 5 mean showing near perfect allignment for a storm..

Steve...my excitement meter is hurtling off the scale..wife thinks ive gone loopy lol.

Ps she'd be right.

Onto ens..hope 18z is a mild outlier.

Edited December 1, 2017 by northwestsnow

[Met4Cast]

Just now, East_England_Stormchaser91 said:

Wonder if this will be rivalled, the blizzard of 30 December 1962! 

Also a deep concern that many of the most recent drivers have never experienced driving in snow at all, let alone drifts of it! 

Passed my driving text back in August so I'm one of those new drivers, I think my biggest issue is going to be other drivers doing ridiculous things whilst driving about, though

[feb1991blizzard]

Another stonking GEFS 850 graph / snow percentage coming up.

[northwestsnow]

Just now, feb1991blizzard said:

Another stonking GEFS 850 graph / snow percentage coming up.

[Ice Day]

6 minutes ago, feb1991blizzard said:

Another stonking GEFS 850 graph / snow percentage coming up.

Jesus wept man......I'm trying to go to bed here!  I'm going to have to have a look now!

Edit - having had a quick check, nearly every pert shows some type of northerly at 150. I'll take Pert 8 please.

Edited December 1, 2017 by Ice Day

[feb1991blizzard]

Mean briefly hits -8c for Manchester, must be some genuine flatiners (-10c) in there.

[East_England_Stormchaser91]

2 minutes ago, Danny* said:

Passed my driving text back in August so I'm one of those new drivers, I think my biggest issue is going to be other drivers doing ridiculous things whilst driving about, though

Indeed. A little knowledge can be a very dangerous thing. 

About time we had a decent amount of snowfall, as it will at least show the newbie drivers what it's like and how to deal with it carefully. 

[northwestsnow]

2 minutes ago, feb1991blizzard said:

Mean briefly hits -8c for Manchester, must be some genuine flatiners (-10c) in there.

In the midst of my unbridled excitement im forgetting EC is not showing anything like GFS...

Gona have to be an all nighter...i dont want to watch 00z incase i jinx it.

[Nick F]

12z GFS op wind speed, was off the scale on 8/12 when it has its day-after-tomorrow superstorm, clear outlier for depth then ...

[snowbunting]

Phenomonal runs from all models. Looking at Nlys next week from wednesday onwards for us up in tbe western isles. We do need to be careful of that low pressure around the 8th. The 12z had it superdeep/extreme and given the different in temp between North and South.. I eouldnt be surprised to see severe gales for the UK... where is anyones guess!

 

Nick that superstorm is just a breeze for us hardy folks on the Isle of Lewis. Lol

 

 

[nick sussex]

Before everyone starts dusting the sledge off I'd urge a lowering of expectations given not just the timeframe but the disagreements between the big 3.

Even if all 3 agreed at this range the low track and highest risk area will likely change between outputs. These set ups are notoriously difficult to forecast with much accuracy 5 days out.

 

 

 

[comet]

There are some cracking ensembles to view. After the bareness of the last 4 winters an almost countrywide snow event bringing 6 to 12 inches of snow would go some way to compensate but if it all implodes and we end up dry and cold with the wishbone effect then that would really rub salt into the still open wounds of the last few years.

[steveinsussex]

we get huge downgrades 24 hours out at times so fully expecting big changes over next few days

[Man With Beard]

The key to next Thursday/Friday is the timing of the Atlantic low hitting the cold coming in from the north. The GFS 18Z and UKMO 12Z were pretty much a bullseye. Still 5 days out though - if that bullseye is still being hit in 48 hours then get the sledge ready - even if it isn't the bullseye, some parts of the country will probably go white anyway.

BTW, ECM ensembles don't really amplify as much as the others by T168 (op well supported tonight)

but the pattern of deep trough east or over us, ridge west gets set by D10

leaving us coldies but reliant on the build up of a cold pool in advance for further snow events - probably just on the wrong side on this run but it's close

[weathermadbarnsleylad]

2 minutes ago, nick sussex said:

Before everyone starts dusting the sledge off I'd urge a lowering of expectations given not just the timeframe but the disagreements between the big 3.

Even if all 3 agreed at this range the low track and highest risk area will likely change between outputs. These set ups are notoriously difficult to forecast with much accuracy 5 days out.

 

 

 

Hi I'm new to this but would it be better to see if the low/northerly still shows after the weekend say 12z sunday/00z Monday to have some confidence in the output. We have all been here before and not all models agree. I love the snow and cold but it scares me to get too excited so I lower my expectations so I would wait while after the weekend what's your take on this nick regards stefan .

[Rollo]

I am one of the dying band of those members who actually were around in December 62', I have to say there is a growing familiarity with the charts being thrown out by the GFS. To expect a similar winter is still very far-fetched and to predict one would put one into the James Madden category!

I thoroughly enjoyed  that winter and 57 years later would be happy to experience another but be warned the traffic chaos would be much worse and power cut would be awful bearing in mind the low temperatures, the weather will do what it does but we should be all aware of what we are wishing for.

Edited December 1, 2017 by Rollo
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