Model Output Discussion 4th Dec.2013-12z onwards.

[SMU]

That would be very transient as the next LP flattened any ridging.

 

depends the angle of the jet into the Low-

 

A Low exiting the US can serve to pull back the parent low over Iceland if they are angled in to each other & there is scandi ridging-

 

If you look at some of the classic scandi high developments its been with a whopping great vortex in the atlantic- then the next day that low has been smacked back to Canada.

The ECM OP 00z was trying that at 192, but didn't quite get there-

 

The UKMO 12z is excellent from that respect. GFS a lot flatter & faster.

[nick sussex]

The ECM at T144hrs certainly an improvement on the 00hrs run, interesting little gap opening up to the ne of Scandi.

[Ali1977]

I think some changes to cold runs are just around the corner, maybe even this ECM run. That low seems to be dragging in NW winds at 144....

[SMU]

http://www.meteociel.fr/modeles/ecmwf/runs/2013121012/ECH1-144.GIF?10-0

 

Quite an exciting chart-

 

S

[TSNWK]

ECM 144 looks teezy... Drum roll to 168

[Barry12]

Much colder in just 6 days with North-Westerly winds

 

[Ali1977]

I wonder if that Azores high could ridge towards Greenland also....

[Ian Brown]

Forgive me if I don't join the excitement. The jet is rolling over the top of any ridging whether it's the Azores or Scandi.

[IDO]

Shame we cannot take the CFS seriously: 

 

Christmas Day:   

 

Atlantic trough till early New Year with a Scandi High (sinks eventually): 

 

It is caused by part of the PV escaping and sinking south into mid Europe allowing the UK high to push NE and link with the Russian High; plausible enough:

 

Edited December 10, 2013 by i'm dreaming of...

[TSNWK]

Nope 168 is disappointing chart from what was shown at 144

[Panayiotis]

Nice NW winds at 144hrs bringing widespread -4C uppers across UK: 

I dont get why people were expecting anything better for 168hrs?...

Edited December 10, 2013 by Panayiotis

[Barry12]

Under -4's by 168

 

[R.P. McMurphy]

Forgive me if I don't join the excitement. The jet is rolling over the top of any ridging whether it's the Azores or Scandi.

Agreed.

 

I dont see what the excitement is here... it's certainly not enough to wet my appetite anyways...

 

While that PV remains that strong, were going to get little if any in the way of snow & real cold.

[Mucka]

Personally I would forget anything in the 5/6 day time-frame as far as looking for a potential cold pattern to set up, it is around day 10 to 12 where there is a small chance of some developments with a possible trigger low diving South. This has been hinted at as a possibility in ECM and GFS output but still a longish shot IMO.

Hope to see some sign of that in tonight's ECM 12z 216/240 charts soon 

[nick sussex]

The ECM is far more favourable than the GFS towards the ne, the Siberian ridge there could put some forcing on the PV. We await the T192hrs with trepidation! or relief!

[TSNWK]

Nice NW winds at 144hrs bringing widespread -4C uppers across UK: 

I dont get why people were expecting anything better for 168hrs?...

When things are this dull, a little break from the boredom is a treat I guess.

[Catacol]

http://www.meteociel.fr/modeles/ecmwf/runs/2013121012/ECH1-144.GIF?10-0

 

Quite an exciting chart-

 

S

 

Dont see it... unless you are referring to a wedge of the vortex heading over towards Tibet. A good hit on a mountain range with some consequent Strat feedback might be cause for celebration but I simply cannot see any teleconnective support for that chart to lead to a proper block.

[Captain Shortwave]

The ECM has downgraded the ridging towards the pole over Siberia...

what a surprise 

As for us, another Euro high but with us under a more unsettled pattern to what we are currently experiencing.

[R.P. McMurphy]

T192 is horrible if it's cold weather you are after... Euro HP.

[Ali1977]

216 surely has potential though

[SMU]

ECM tonight is slightly flatter tonight- but keeps my interest-

 

As said about the ridging

 

http://www.meteociel.fr/modeles/ecmwf/runs/2013121012/ECH1-192.GIF?10-0

 

to

 

http://www.meteociel.fr/modeles/ecmwf/runs/2013121012/ECH1-216.GIF?10-0

 

to

 

http://www.meteociel.fr/modeles/ecmwf/runs/2013121012/ECH1-240.GIF?10-0

 

 

UKMO would be better-

 

S

[Mucka]

Just what I was hoping to see.

 

 

Looks like some good undercut on the way, we would have a chance from there.

Trouble is, can we trust the output?

Edited December 10, 2013 by Mucka

[mulzy]

216 surely has potential though

Yep, a little tweaking of the 216 and 240 charts and we're in business.  All FI of course!

[nick sussex]

Regardless of the post 168hrs output the models are a bit more amplified upto that point than they were a few days ago, nothing great in terms of cold but maybe we can build on some of the earlier better trends.

 

The ECM still wants to dig that troughing south later and cut the limpet high, given what the outputs looked like a few days ago this is a slight improvement and the T240hrs show potential.

 

The issue is the upstream amplification as to whether the ECM is overplaying this, is the GFS too flat?

 

Overall my horror rating this evening drops from 8/10 to 7.5/10.

[snowmadchrisuk]

Yeah +240 sends the pv back West . Allowing ridging . Well done Steve