Model output discussion - Closing in on Christmas

[alexisj9]

1 hour ago, Jason M said:

Yep, get that. 18Z ikon runs out to 120 hours so its impossible to be definitive but my own (possibly wrong)  view is that we still end up with similar to what's being shown elsewhere by day 8 or 9. Either way, we will probably know soon enough. 

The difference is in our weather, we either get cold quicker, with shallow Azores low, or a storm which delays the cold.

[lamppost watcher]

34 minutes ago, Griff said:

Just not having to see the in laws makes up for some of 2020

 

[Allseasons-Si]

4 minutes ago, Ice Day said:

Here's the next northerly, the New Year's Day Blizzard (well for the Highlands of Scotland anyway).

And more is following

a great run,...in in the midst of heaven nania gates to become the gate of the garden path in the morning,will shall see

again,goodnight from me.

Edited December 17, 2020 by Allseasons-si

[ICE COLD]

The pv is looking in serious trouble on the last few op runs . 

[Uncertainty]

6 minutes ago, Mapantz said:

A clear trend South by the 23rd, with the control and mean following the OP - looking at the London 850 ensemble so far..

FI at day 4 though!

 

Yep but need it south on ALL major models tomorrow to be safe, especially and obviously the ECM.

Bear in mind GEM also has the secondary low and lots and lots of rain. These two models together represent a significant element of NOAA and, presumably, Exeter’s musings...

Edited December 17, 2020 by Uncertainy

[Matt H]

GEFS 18z ensembles look cold for the Christmas period with the mean touching -6C and many other members reaching -8C. Great trends!

[feb1991blizzard]

35c about 170000ft!!!!! @Scorcher

[alexisj9]

56 minutes ago, Mike Poole said:

Next attack right in behind T162, and from the earlier runs that is the is one to watch:

Looks to me like the trough near USA is going under the high here.

[Ice Day]

1 minute ago, Frosty Winter said:

GEFS 18z ensembles look cold for the Christmas period with the mean touching -6C and many other members reaching -8C. Great trends!

Certainly are looking good, different view here:

(These are for my location - colder further north!)

[northwestsnow]

You can be sure further North will be colder on 18z GEFS...

Really hoping UKMO has this and the rains stay away...

Edited December 17, 2020 by northwestsnow

[weirpig]

Crikey -10  hitting scotland on the control at  228

Edited December 17, 2020 by weirpig

[Mike Poole]

Now where have I seen that before?

[kumquat]

11 minutes ago, Frosty Winter said:

GEFS 18z ensembles look cold for the Christmas period with the mean touching -6C and many other members reaching -8C. Great trends!

That's MY kind of spaghetti. Cold and sticking to the bottom of the pan!

[Daniel*]

5 minutes ago, Frosty Winter said:

GEFS 18z ensembles look cold for the Christmas period with the mean touching -6C and many other members reaching -8C. Great trends!

But no it can’t... it will water down on the day before !  

[Johnp]

By the end of the run, all of the UK is buried in snow, apart from south of

ThE m4 CoRridOr! 

Edited December 17, 2020 by Johnp

[weirpig]

For those wishing to satisfy there snow fix  Control  recommends   that  you visit the snow ridden plains of Morroco  or Algeria.  

Cold air way south

[Catacol]

Moved house today. Chaos. Popped in now for a quick look at various bits of data to see this GFS chart for Xmas day. Not much needs saying other than - Yee Haar! It’s still too far out to be served with clotted cream and a dollop of jam....but it’s a damned tasty looking setup for sure!

All the key elements are there. Siberian High edging to the Urals....trough dropping into Eastern Europe, obvious open door up into Greenland, clear wave break eddy effect on the back of the next momentum spike producing a highly amplified pattern. 

And the Berlin charts have renewed wave 2 impacts arriving at day 10.

There is a long road yet to travel, but it would be great for all amateur weather watchers and snow hunters if the best computers running the highest powered seasonal forecasts could be put to the sword. What will happen to our fun if NWP output starts to nail every season?

A split style SSW is very much on the cards for January. If so, somewhere in the northern hemisphere will be staring at some extreme cold conditions inbound.

In the shorter term our coldest tropospheric led output for many a December is looking likely. Happy days.

 

[rug]

I hate the M4.

[Daniel*]

Major SSW written all over it on GFS 18z and perfect timing wouldn’t that be in early January? 

[kumquat]

5 minutes ago, Johnp said:

By the end of the run, all of the UK is buried in snow, apart from south of

ThE m4 CoRridOr! 

The Marrakesh Express arrives and The High Atlas get their early ski season. Meanwhile Somerset Levels are flooding like in 1607 

 

[Uncertainty]

Trop and Strat jets mirroring each other in the Atlantic sector on the back end of the 18z

Polar Northwesterlies it is then!

Plenty of warming too. It’s hard not to get excited by the output at present. 

@Catacolnailed it and as I’ve said before. If the good weather folk beat the Scroogey  seasonals with a split SSW for Jan it’ll be a real coup. But don’t forget, each synapse is effectively a quantum bit. They’ve got a way to go before they can outthink the peoples lol.

If we do get this SSW, surely the big +EAMT is playing a big part.

Finally, this our bog standard Christmas week singularity anomaly

Except, the colours seem to have swopped

 

Edited December 17, 2020 by Uncertainy

[Sperrin]

43 minutes ago, Ice Day said:

Certainly are looking good, different view here:

(These are for my location - colder further north!)

Does anyone have a link to these charts please?

[Roger J Smith]

The 18z GFS may just be off on one, but it does have the benefit of late breaking data input from the monster snowfall event in the interior northeastern U.S. which must be a factor in why it appears to change the evolution of the 22nd-23rd low pressure in the UK region. 

Will be interesting to see if these trends (which have shown up in various forms in a few past runs of the GFS) are maintained at 00z, or if that reverts to the brief shot of northwesterly cold and mild west-northwest fast flow scenario that the ECM seems to favour so far. Even the 12z GEM wasn't going anywhere near as cold as the 18z GFS. 

Verbatim, that 18z GFS would be a 2-4" snowfall followed by waves of bitter cold topped up by intervening 1-2" snowfalls (in most places, obviously more from any Irish Sea streamers hitting Wales or southwest). Only about 30% confident that it might be close to real however. 

[SLEETY]

Gfs doing what it does best, I think it's the programmers, garbage in garbage out, that might explain its wild swings every 6 hours

[Daniel*]

32 minutes ago, Sperrin said:

Does anyone have a link to these charts please?

Meteociel.fr - Tableaux GEFS v12

WWW.METEOCIEL.FR

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