Model Output Discussion - Winter arrives

[johncam]

Guys would GEM go the same way after 240 as the GFS ?

[minus10]

YUCK, YUCK and treble YUCK !!!!!

[Staffmoorlands]

4 minutes ago, johncam said:

Guys would GEM go the same way after 240 as the GFS ?

Probably, and push up some mild southerly's too.

[johncam]

On 07/12/2021 at 17:46, Staffmoorlands said:

Probably, and push up some mild southerly's too.

Thanks for reply

[Anthony Burden]

Evening all,All minds on what happens next after the Atlantic calms down,pressure rise looking a good 

bet.GFS keen on the French connection with a mild southwesterly start,that will alter along with ECM and

others.Patient’s is required to far out at present to nail down but an evens bet that a cold scenario could

well be the final outcome.The bookies are given 5 to 1 on a white Christmas so they may know something 

we don’t know.

 

[NewEra21]

Not a good set of runs this afternoon, but luckily it's all far into fantasy land to worry about too much. 

But as we've seen from this afternoons runs, everything hangs on how this potential high positions itself. All options are available and I'm sure in the days and model runs ahead, we'll continue to see all the good and bad possibilities. Gonna be a lot of ups and downs to come!

Edited December 7, 2021 by NewEra21

[Captain Shortwave]

Not much to report, week two still looks to be turning drier and more settled as high pressure builds across Europe.

GEFs

 

Looks settled in the south, more runs needed to see if this trend pushes northwards. Any northwards push would increase the chances of a drier continental feed (mild if southerly but chillier with any easterly element).

GEM looks a decent fit for a solution getting more north.

 

At the moment it is a case of being patient, though at the moment I think anything white for Christmas will be more likely to be frost or fog. That said an evolution like this could bring something more interesting if cold air aloft is able to brought westwards as opposed to a surface chill.

 

[MATTWOLVES 3]

30 minutes ago, Anthony Burden said:

Evening all,All minds on what happens next after the Atlantic calms down,pressure rise looking a good 

bet.GFS keen on the French connection with a mild southwesterly start,that will alter along with ECM and

others.Patient’s is required to far out at present to nail down but an evens bet that a cold scenario could

well be the final outcome.The bookies are given 5 to 1 on a white Christmas so they may know something 

we don’t know.

 

No mate they know nothing,we get odds of that and shorter every year for a white Xmas...they most certainly are Express readers.

I would say settled with night Frost is the most likely option as opposed to falling snow...long way off,but unlikely imo.

[Ali1977]

Blocking option increase again in the GEFS FI charts 

[Kasim Awan]

Getting somewhere. 

[Met4Cast]

A horrible set of models today but anything beyond day 5-7 at the moment should be viewed with a bucket load of salt, models are going to be resolving the MJO phasing and figuring out how this plays into current westerly momentum we're seeing in the jet stream. 

The AAM is slowly on the rise largely thanks to an uptick in FT but also the current MJO phasing, as the MJO transitions to a higher altitude in the next 5-7 days or so this should drive the AAM into positive territory.

The MJO is looking like a slow mover and could loiter around in phase 7 for quite a while, this combined with a +ve AAM puts us in a very good position for a -NAO come late December. 

It'll be a while before models resolve this so expect fairly big swings in the extended, but broadly we want to be looking at high pressure developing to the north-east of the UK in the time period 17th-25th, something I highlighted back in November which now seems to have growing support within some ensembles. 

Whether we can see high pressure develop favourably for advecting deeper cold into the UK remains questionable, but some form of blocking seems almost a certainty at this point, the details however wont be known for a while. 

All in all, despite some NWP outputs, the broader teleconnectives support blocking & potentially colder weather.

P.S. This will be a good pattern for potential PV disruption too.

Edited December 7, 2021 by Met4Cast

[TSNWK]

On 07/12/2021 at 18:43, Kasim Awan said:

Getting somewhere. 

Looks boxed in though! With no opportunity to move north west or north? And being saved from drifting south east by weak energy over the Balkans.  Thread and hanging. .  

[Cold Winter Night]

1 hour ago, johncam said:

Guys would GEM go the same way after 240 as the GFS ?

Probably not.

GEM has the High located no less than 1000km North of where GFS centers it.
GEM also has the High shaped in a more Omega like way, which helps to 'prop it up' from both sides.

The GEM solution is really not bad at all.

[Kasim Awan]

3 minutes ago, TSNWK said:

Looks boxed in though! With no opportunity to move north west or north? And being saved from drifting south east by weak energy over the Balkans.  Thread and hanging. .  

When background signals support retrogression, dissolvement of pressure is possible even where it looks somewhat unrealistic.  Still, I see your point so it could take some time to get the high north enough.

Edited December 7, 2021 by Kasim Awan

[Staffmoorlands]

Just now, TSNWK said:

Looks boxed in though! With no opportunity to move north west or north? And being saved from drifting south east by weak energy over the Balkans.  Thread and hanging. .  

Agree. With the jet to the North powering over  its a sinker in the long run. Still early days though and the met office are going for a cooler Christmas period too

[Captain Shortwave]

A long way off but at least the ECM seems ok with the long wave pattern setting up for week 2.

 

A very deep Atlantic trough should allow the ridge to continue to build northwards. Seems to be a good amount of room to start pulling some Siberian air westwards underneath that ridge and the polar vortex looks a lot less intimidating that it did a day or so ago.

Day 10

[Ali1977]

ECM and GEM singing off the same song sheet here. This would be good moving into Xmas week 

Edited December 7, 2021 by Ali1977

[Kasim Awan]

13 minutes ago, Staffmoorlands said:

Agree. With the jet to the North powering over  its a sinker in the long run. Still early days though and the met office are going for a cooler Christmas period too

I don't see it as a sinker. Plenty of warm air advection and we'd start loosing jet energy - if the ecm ran to 268h there would probably be a further rise in pressure over northern Scandinavia.

Edited December 7, 2021 by Kasim Awan

[Mike Poole]

Just now, Ali1977 said:

ECM and GEM singing off the same dog sheet here. This would be good moving into Xmas week 

Yes, they often do, GEM and ECM.  Happy with that for now, just need to see if it can correct northwards a bit over the course of the next 2 or 3 days runs.  MJO effects have that 10 day lag, so that’s when we are likely to see a change in pattern to something colder, provided of course it isn’t a phantom MJO signal - we’ve had to contend with them over the years!

[Cold Winter Night]

3 minutes ago, Ali1977 said:

ECM and GEM singing off the same dog sheet here. This would be good moving into Xmas week 

ECM and GEM are often close.
This is a good starting point at day 10 IMO.

They are different in the Labrador-Greenland area though.
But with a High near us that has sufficient latitude, a raging tPV between Canada and Greenland is no problem.

 

 

[TSNWK]

On 07/12/2021 at 18:54, Kasim Awan said:

When background signals support retrogression, dissolvement of pressure is possible even where it looks somewhat unrealistic.  Still, I see your point so it could take some time to get the high north enough.

In fairness to  @Kasim Awan center of high did shift about 500 miles north east between 192 and 240.. at 192 I could see no way out.. keeps us on our toes! This model watching

 

 

[Jeremy Shockey]

ECM 12z day 10

The high may be heading in the right direction at least ......something to keep an eye on perhaps

[minus10]

With the high over the other side of the pole ,(Aleutian?), the pole high and the high moving up through scandi could there be a cross polar link splitting the vortex on this ecm run?..

Edited December 7, 2021 by minus10

[SLEETY]

ecm wouldnt take much for high to move further North and bring very much colder air westwards over europe

[Battleground Snow]

Looking forward to BA or mulzy telling us the ECM ext has nudged the high north again