Model Output Discussion - mid Autumn

[That ECM]

Just now, Ramp said:

If there’s a way for it to fail, the uk will find it.

If ever there was a name that was so unfitting.

[Howie]

I'm not worried about those lows next weekend, it will be different next run we all know this lol

[Ali1977]

Don’t worry about only seeing -4c uppers, dew points and thickness look good for snow by Thursday for most of the U.K. 

[TSNWK]

slack air / some snow on the ground in places  / long nights - plenty of -10 and below temps on this night..... will be bitter...

[Howie]

Just now, TSNWK said:

slack air / some snow on the ground in places  / long nights - plenty of -10 and below temps on this night..... will be bitter...

We saw similar last year

[Ali1977]

1 minute ago, TSNWK said:

slack air / some snow on the ground in places  / long nights - plenty of -10 and below temps on this night..... will be bitter...

Yeah definitely, especially with any m snow cover looking forward to the ECM 

[danm]

1 minute ago, Ali1977 said:

Don’t worry about only seeing -4c uppers, dew points and thickness look good for snow by Thursday for most of the U.K. 

Yep, similar to last December. Sub -8/10c 850’s are typically needed for a convective easterly. With these types of set ups, not so much. 

[Geordiesnow]

Charts are starting to remind me of December last year where whilst the 850hpa temperatures are nothing to write home about however because it's quite slack, we could see some quite sharp frosts at night aswell for some. 

Snowfall looks extremely limited to me going by the outputs so if your after that then I wouldn't build your hopes up really.

[TSNWK]

Just now, Ali1977 said:

Yeah definitely, especially with any m snow cover looking forward to the ECM 

which might be a question for in between model runs  - if uppers are say -5 why is it you can temp's below the uppers?

risk of West NAO here - 

[swfc]

Hmm gfs 12z at day ten looks epic with the heights to the north and low pressure across the uk etc. Now if it was January

[Met4Cast]

One question I have is how sustained can this blocking become? We know the teleconnective drivers aren't in favour of this but through what appears to be pure chance we've seen a wave-breaking event at the exact right time to throw up this high-latitude blocking.

Now.. with the likely return of an active jet into early December on the back of -AAM tendency & MJO transitioning phases 1/2/3. if blocking is somehow able to take a quasi-stationary residence to our north this may south shift the more active jet stream, we then see the Canadian warming kicking in which helps to reinforce any blocking. 

By mid December MJO should be cycling into more favourable blocking areas with a switch to +AAM tendency.. very, very interesting times.

[Battleground Snow]

Nice gem, cold will develop in situ as mentioned earlier 

[Kentspur]

5 hours ago, topo said:

GFS 06z is probably one of the coldest model runs that I have seen for my area and southern Scandinavia. 

 

My first day in Stockholm on most models and ensemble suites Tuesday is showing a max of -5c and heavy snow I wonder when the last time that happened in November was?

[swfc]

7 minutes ago, Met4Cast said:

One question I have is how sustained can this blocking become? We know the teleconnective drivers aren't in favour of this but through what appears to be pure chance we've seen a wave-breaking event at the exact right time to throw up this high-latitude blocking.

Now.. with the likely return of an active jet into early December on the back of -AAM tendency & MJO transitioning phases 1/2/3. if blocking is somehow able to take a quasi-stationary residence to our north this may south shift the more active jet stream, we then see the Canadian warming kicking in which helps to reinforce any blocking. 

By mid December MJO should be cycling into more favourable blocking areas with a switch to +AAM tendency.. very, very interesting times.

Good post. Whatever the background signals are the atmosphere will do its dance. Hence a 48 hour forcast ie sliders/rain-snow are projections

Edited November 24, 2023 by swfc

[Mike Poole]

GEM has a decent run, doesn’t quite make as much of the first low near Scotland around the T120 mark as the GFS, but more than UKMO or ICON, then very good coverage of cold by T180 in NE flow:

[Mike Poole]

UKMO T168 very very good:

Very clean run this, I always want to see the UKMO on board, if it is wobbly, ignore it at your peril in situations like this!

[Mcconnor8]

2 minutes ago, Mike Poole said:

GEM has a decent run, doesn’t quite make as much of the first low near Scotland around the T120 mark as the GFS, but more than UKMO or ICON, then very good coverage of cold by T180 in NE flow:

Like that GEM run a lot, cooler uppers than most models

[phil nw.]

Granted it is day 7 but this is what I like as Gfs shows the pattern developing nicely.

Phasing the Euro trough with the Scandinavian trough as the core of heights established towards Greenland.

This replenishes the cold from the north east and nudges the jet south.

[tight isobar]

Some pretty astounding runs this evening- especially just opening the door to winter- And as again, with such Synoptics expect those 850- inflow to continue the down drive into the UK..

[Dennis]

more fights ahead 

 

[Lukesluckybunch]

Not a bad way to spend Friday evening,looking at these models particularly UKMO at 168 looks brilliant..and now waiting for the ECM to come out..this cold spell coming is looking pretty decent,nothing too severe just yet!but colder then average certainly!

[Biggin]

25 minutes ago, TSNWK said:

slack air / some snow on the ground in places  / long nights - plenty of -10 and below temps on this night..... will be bitter...

Any idea of the track of that low or will it disappear

[ANYWEATHER]

19 minutes ago, swfc said:

Hmm gfs 12z at day ten looks epic with the heights to the north and low pressure across the uk etc. Now if it was January

Actually, perfect for snow chances,  I would think due to low solar output ,and relatively warm SSTs ,creating instabilty and with Artic air becoming entrenched across the UK ,some folks on the coast may well see Thundersnow ,yes thunderSsnnnaaawww ! Gfs 12z, is a peach of a run for coldies up to the T+240 hrs and beyond.  Of course ,forecasting snow, saying where it will fall and where, is a mugs game, but next week is looking primed to kick off Winter in true style ,looking the best start to winter since 2010!

[Methuselah]

TBH, and no offence meant to anyone, I'll start taking all this hype seriously, the moment I can wipe the astoundingness off my living-room window. . . Meanwhile it's a case of 'a million times bitten, a million-and-oneth-time shy!'  

[Chasbrown]

Daily Express hasn't mentioned anything about the weather yet which I take as a positive omen!