Model Output Discussion. 3/12/2022. How cold will it get?

[nick sussex]

1 minute ago, That ECM said:

Differences are crazy.

I think I was being too kind to the UKMO . I’ve downgraded it further from SSO to SG , Synoptic Garbage !

[BlueHedgehog074]

The operational models do love to keep many on their toes

[Derecho]

3 minutes ago, Captain Shortwave said:

The UKMO looks like it has gone rogue at day 5. The concern is that the physics pulling the cold air into the Atlantic is going to engage that Azores low causing it to deeper and move in an increasingly northerly manner.

The GFS is nowhere near this, block to the north east could do with a bit more juice (cold) though.

Yeah it's a complication, should be ok if we get the Azores Low going under however?

[northwestsnow]

Well, clear as mud this evening!!

Next !!

[Johnp]

What time does the UKMO 168hr chart come out please?

[Nick F]

So, on 12z GFS the original large Azores low drifts towards New Foundland while spawning a secondary low near the Azores that does head towards western Europe into Bay of Biscay out of harm's way, you couldn't predict this stuff!

[Captain Shortwave]

GEM - Another 6 day solution

Any heights for the north east being a blink and miss it affair with cold pushing down from the north.

[northwestsnow]

Just now, Johnp said:

What time does the UKMO 168hr chart come out please?

5pm I think..

Does look an odd run but I'm hoping the low keeps south regardless..

[nick sussex]

1 minute ago, Nick F said:

So, on 12z GFS the original large Azores low drifts towards New Foundland while spawning a secondary low near the Azores that does head towards western Europe into Bay of Biscay out of harm's way, you couldn't predict this stuff!

So far it seems the Hollywood scriptwriters have hacked the NWP models!

Edited December 6, 2022 by nick sussex

[Downburst]

Just now, Nick F said:

So, on 12z GFS the original large Azores low drifts towards New Foundland while spawning a secondary low near the Azores that does head towards western Europe into Bay of Biscay out of harm's way, you couldn't predict this stuff!

I am not sure if you are being Ironic there Nick. I had the models could predict it with some accuracy.

[Johnp]

Just now, northwestsnow said:

5pm I think..

Does look an odd run but I'm hoping the low keeps south regardless..

Thanks.  I think Miss Shannon Entropy has entered the building. 

[Singularity]

Compared to the GFS and GEM 12z runs the 12z UKM is both much quicker to move the low crossing the Azores east and keener to peel off a low from the trough across the UK and send that west.

The resulting situation at +144 is so very complicated... what happens next will depend on whether the little feature northwest of the main low his sufficient to out-muscle the Scandinavian high and pivot that around, sending it ENE. That high will also be attempting to head a bit west as the smaller northern low heads W or SW.

I really don't feel inclined to trust it with the speed of the low across the Azores, though. For a while now we've been looking at a Wed-Thu closest pass to the UK but this run has it knocking on the door as of noon Mon!

I'll give it more credence if ECM turns out even loosely similar later, though.

[Johnp]

GEM isn’t hanging around and wants to send the mother load our way

[Battleground Snow]

3 minutes ago, Captain Shortwave said:

GEM - Another 6 day solution

Any heights for the north east being a blink and miss it affair with cold pushing down from the north.

I think I prefer gem solution over the other 2, less pitfalls and look at the depth of cold waiting in the wings to the north!

[Panayiotis]

Heights building over UK which should topple over Scandi, undercut low and BFTE later on in the run? Dream chart viewing....

[Ben Sainsbury]

Just now, Johnp said:

GEM isn’t hanging around and wants to send the mother load our way

The end of this run *could* be spectacular.

[Mark wheeler]

Such differences on the 3 models coming out on the 12z so far .  Day 6 is anyones guess at the moment, very interesting watching all the same .

[Singularity]

Just hit me that this fast possible (or I daresay probable?) bias from UKM with the low across the Azores was also there on the 00z run. Even compared to the ECM 00z it was way quicker. Either on for a massive win or humongous fail versus the other 'main' models (ECM, GFS, GEM).

[tight isobar]

Your- NOT going to find clean Synoptics- when there is such filth involved!.. leader lp still imo looks for uk engagement, the ukmo is losing its sync @D-6 and quite expected!.. we’ll know a lot more against the 12z suites when the mother AMP model sheds its skin this evening @12z ecmwf!

Edited December 6, 2022 by tight isobar
Miss spelled

[Johnp]

If possible, I think we’ve gone backwards today (not with regards cold, but with knowing how this is likely to play out). 

‘tis all part of the fun I suppose

[weatherguy]

With the trop PV in its current state, and the usually-ever-present Canadian PV lobe conspicuous by its absence, the Atlantic jet simply doesn't have the strength for LPs to make much of an inroad into the cold established over NW Europe.  As a result, it's logical that those LP systems slide south.  This is good for those wanting snow a chance at more significant snowfall, as it introduces moisture into the area - we don't have raging convective easterlies showing just yet in the reliable timeframe, though of course that may yet be the end result here.  

We see this on the UKMO at +144 (to a lesser extent though), GFS at various times (+210 shown), and on the ECM 0z at 216h

[booferking]

My money is on the gem outcome short Easterly then look to the north the azores low is not getting anywhere close to the uk, gfs had the same issue early last week dropping the trough from the North and its repeating this error again the difference is night and day between gem & gfs also the ecm was first to pickup trough dropping from the North last night 

Edited December 6, 2022 by booferking

[bluearmy]

Ukmo day 6 brings the low across and the snow line central midlands (Norwich to Birmingham) 

[swfc]

I've kept my powder dry tbh for a good few days. Firstly the 12 z ukmo looks wrong. I've been following it for 7 days

For me the GEM /ecm will be the closest to a representative outcome with all caveats. If not the beers are on me

Edited December 6, 2022 by swfc

[northwestsnow]

I have literally no idea what UKMO 168 would look like on the ground..