Model Output Discussion - cold spell to end Autumn

[northwestsnow]

UKMO looked poor at 120 but the 144 chart looks OK? Cold air filtering back south...

[Daniel*]

4 minutes ago, snowray said:

Liking the look of the 12z, could be very snowy from the Midlands north on Sunday on this run. 

You’re from Kent what bloody good is that.

 UKMO a complete and utter messs a rain fest for most, it’s never easy it? 

[MKN]

8 minutes ago, snowray said:

Liking the look of the 12z, could be very snowy from the Midlands north on Sunday on this run. 

Blackpool across to Hull northwards more like. Certainly nothing for the Midlands.

[snowray]

Could be a lot of snow around this weekend, North East looking best to start with, then the cold air digs back south and so does the snow risk. Pretty happy with this sort of outcome, bit of snow for most of us and staying very cold out to T144.

[Devonshire]

2 hours ago, Southender said:

Something like this?

http://www.meteociel.fr/modeles/gfse_3d.php

thanks Southender - looks interesting, but not quite what I was thinking of (unless I just couldn't see the controls) - I was thinking of a model that would allow you to slice down through one 3d image (taking a vertical section or plane, if you like, so as to see what is happening at different heights) - I realise that it would require a lot of data/bandwidth to do in realtime. I have seen some 3d representations of what happens to the vortex in a warming event somewhere - a smaller representation of different sliders over the UK is what I would find very interesting...

[terrier]

9 minutes ago, snowray said:

Liking the look of the 12z, could be very snowy from the Midlands north on Sunday on this run. 

Looks like quickly turning back to rain aswell. No thanks. 

[Day 10]

What a nightmare to forecast!

[winterof79]

2 minutes ago, frosty ground said:

I think it will have another go later..... not that it will look anything like this in the morning.

I would assume that is a very cold chart 

[mountain shadow]

2 minutes ago, terrier said:

C. Will it be cold yes. Will it be widespread snow and locked in cold spell. 

Bar a few GFS runs, I haven't seen any evidence of this, so I'm unsure why you think there should be widespread snow.

A cold spell is locked in, temperatures will be below average for most for some time. It ain't December 2010.

[frosty ground]

1 minute ago, terrier said:

Looks like quickly turning back to rain aswell. No thanks. 

 And then back to snow.......

[Singularity]

2 minutes ago, northwestsnow said:

UKMO looked poor at 120 but the 144 chart looks OK? Cold air filtering back south...

850s not as bad as I expected actually - though the wind direction is certainly poor at +120 so it only means a chance of leading-edge snow with a bit of luck (at least on high ground).

The +144 saw the Canadian vortex move as hoped which improves the upstream look again although it's not as pronounced as I'd have liked to have seen from the model this evening.

I must say, this period of model watching is much easier on the likes of me living in the far-south at low elevation, where the snow chances are minimal anyway .

[winterof79]

3 minutes ago, terrier said:

Looks like quickly turning back to rain aswell. No thanks. 

You seem to have quoted on  a 12z chart followed by a 6z chart.

The snow lasts much longer on the 12z

Edited December 5, 2017 by winterof79

[SMU]

UKMO Recovers although a frustrating 120 chart

GFS VERY good all the way for midlands North - a slightly milder blip for the SW

UKMO is the eastern point of the cone, The GEM is the western point-

GFS still pumping out some deep cokd minima next week !

[Weathizard]

If only that wretched piece of vortex would take a hike from Eastern Canada/Western Greenland. 

[northwestsnow]

Prayer mats out for GFS then !! 

The uppers on ukmo actually dont seem as bad as i thought they might, hmmmm, colder air moving back south at 144 perhaps?

 

 

[northwestsnow]

2 minutes ago, Steve Murr said:

UKMO Recovers although a frustrating 120 chart

GFS VERY good all the way for midlands North - a slightly milder blip for the SW

UKMO is the eastern point of the cone, The GEM is the western point-

GFS still pumping out some deep cokd minima next week !

I agree steve- i'm not sure how much truck we should out in that ukmo run, the progression from 120-144 looks a bit iffy (although in a good way)..

Think elevated parts of the north would do OK on ukmo , just my two penneth.

[terrier]

I certainly won’t be placing my faith in the gfs with its verification stats. Think ukmo will be nearer the mark. Let’s see what the ecm thinks a little later. But expect it to follow something like the ukmo is showing.

[northwestsnow]

7 minutes ago, frosty ground said:

 And then back to snow.......

FG with your altitude i think you might get a whole lot of snow over the next week or so....

certinly if GFS is correct- although ukmo might produce for you too...

[snowray]

OMG, anyone seen the GEM? Talk about a mega coldaholics fix, Dec 1981 re-run!

[frosty ground]

1 minute ago, terrier said:

I certainly won’t be placing my faith in the gfs with its verification stats. Think ukmo will be nearer the mark. Let’s see what the ecm thinks a little later. But expect it to follow something like the ukmo is showing.

A week a Saturday why not reproduce the Verification stats to see how each model is doing in this set up?

[Captain Shortwave]

UKMO/GFS/GEM at day 5

     

Well on a global scale there is very little between them, but on the UK scale the differences are stark.

UKMO - The low disrupts far too late so probably rain for most with a chilly NW flow to follow.

GFS - The Low disrupts move favourably, and snow/rain/snow event with Yorkshire being the winner with aroud half a foot of snow forecasted from the GFS (Not that snow depths are reliablebut a believable total given the heavy precipitation).

GEM - The best of the bunch in terms of keeping the UK in the cold air, but only southern counties recieve anything from this low and the snow grazes the south coast.

The flow tends to slacken by the middle of next week so pretty dry inland but with some severe frosts under a slack pattern.

Edited December 5, 2017 by Captain Shortwave

[Weathizard]

3 minutes ago, snowray said:

OMG, anyone seen the GEM? Talk about a mega coldaholics fix, Dec 1981 re-run!

Shame the GEM is an absolute train wreck just lately, used to ne alright. Suppose it does show that it's not game over just yet for us Sunny southerners 

Edited December 5, 2017 by Weathizard

[Chris.R]

Again,  absolutely wonderful post earlier by @Bring Back1962-63. Post of the month!  Thanks so much for taking the time to write it.  Some of these posts  should be put in the learning area as well. :-). 

[snowray]

15 minutes ago, Daniel* said:

You’re from Kent what bloody good is that.

 UKMO a complete and utter messs a rain fest for most, it’s never easy it? 

Well at least some of the country will get a snow fix, I want everyone on here to get some snow, I fully expect to see some of the white stuff even around here at some point in the next week.

[Singularity]

LP from the NW seems excessively developed which is a shame as  the broader-scale pattern is improved from the 06z and 00z with the Canadian trough further S and a little W plus orientated better for rebuilding the mid-Atlantic-Arctic-High linkup. This should still unfold but after an unwelcome interruption (unless you enjoy chilly rain being thrown in your face).