18z GFS(P) producing another variation on the same theme of mid-Atlantic blocking

ECM 12z ensemble for London shows a further strengthening of the signal for cold conditions from later next week. The operational was amongst the milder options.

Are you sure Rob very active cold front moving south

 

 

 

Looks like 'Polar low' haha!

Rain to snow event or thundersnow? Cold air behind that front!

That couldn’t look less like a polar low if it tried. 

Some sort of vague consistency and agreement starting to show in the ens cross-model. Mind you, compared to the last few weeks that’s not difficult. 

Love the Parallel run:

Variation of the 12z run! A Polar Low? Polar Low?

But if this did come about this would be quite a shock a blast?

Blizzards for the south west if this verifies?

That couldn’t look less like a polar low if it tried. 

Some sort of vague consistency and agreement starting to show in the ens cross-model. Mind you, compared to the last few weeks that’s not difficult. 

Have you a view on the Brexit situation too Matty 😉

Good to hear from you by the way 😊

That couldn’t look less like a polar low if it tried. 

Some sort of vague consistency and agreement starting to show in the ens cross-model. Mind you, compared to the last few weeks that’s not difficult. 

Icelandic Low?

 

Have you a view on the Brexit situation too Matty 😉

Good to hear from you by the way 😊

Political discussions are for people who enjoy pointless confrontation, mate 

Cheers Neil. Good to see you still prevalent on here. Your measured posts have always been one of the better reads. Gavin P, Retron, Shropshire, Gusty and a few others always stand well.

I’m as sure as I can be that Feb will at the very least provide snow potential for all. How much and how long is utter guesswork. 

Last Op run of the day always seems to be amongst the warmest in recent days...not sure why - probably just coincidence....hoping one of the eye-candy perturbations makes 2019 a year for the memory banks: it's in need of something good happening with all the Brexit bothersome-ness, warming oceans and boil-in-the-bag earth beckoning from ostrich mimicking world leaders over focussed on wall building.

Last Op run of the day always seems to be amongst the warmest in recent days...not sure why - probably just coincidence....hoping one of the eye-candy perturbations makes 2019 a year for the memory banks: it's in need of something good happening with all the Brexit bothersome-ness, warming oceans and boil-in-the-bag earth beckoning from ostrich mimicking world leaders over focussed on wall building.

Two will become too Political soon - is there a Politics thread or something Brexit related? Because I can see us and even myself talking politics at some stage with so much going on and the political events that are due to occur over the next few weeks and months that it will be hard not to mention anything political on here or is talking politics forbidden on tow? I remember Gooner mentioned one or two things at one point?

The trend continues on 00z

...and that applies to the ensemble suite too. There's been a gradual rise in the number of sub -10C 850s, but they're very much glancing blows rather than a deep Beast-type setup. Nonetheless, with low pressure close by that 850 level will be hundreds of feet closer to the surface than with an easterly.

At a ground temperature of 3C, 850hPa is around 4900 feet at 1025hPa sea-level pressure. At (say) 990hPa, it's 4000 feet - and that makes a hell of a difference. It's why we're seeing so many runs with snow despite what looks to be on the face of it less than exciting amounts of deep cold air around.

(Click for full size).

Further up, the SSW is of course ongoing. Last night's ECM run extended it until T+216, which is noon on the 20th. This extension, which was hinted at the day before, will just add further impetus towards the pattern change in my view. However, until it goes back to normal (and subsequently flushes down to the lower layers) it's still rather uncertain as to the longer-term effects. I wouldn't be surprised to eventually see a Scandinavian High and easterlies, though that may be a few weeks away yet.

As an aside, it's wonderful to be seeing all this with over half of the meteorological winter remaining!

Ensembles have solidified there position overnight on GFS. Best of the winter so far.

One of the most noteworthy things for me is seeing the mean minima on the London GEFS going below zero consistently at the latter stages. That's very rare this far out and, as you suggest, would point to a very strong cold signal.

Wow.  00z GFS, Operational is looking very interesting for cold and wintry weather.

Cold Arctic air and Northwest to North and NE winds in the bag as well.  I hope the ECMWF, ICON and the UKMO also show and backup something like this for the UK.

Hmm, Oceans warming up more quickly than expected- does google a bell.

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00z ECMWF to T144- at the moment it looks like we need to await to see if like the ICON has it, Cold Thursday 17th, North cold on Wednesday 16th, Less cold Friday the 18th.

If ECMWF at 168- follows the ICON that shows North Atlantic PV Low head to France West NW- it could drag cold and frosty arctic air back in by Saturday and Sunday.

It is less cold ECMWF 00z, so at Friday 18- Saturday 19th the UK looks less cold, with high Pressure. 

GFS and ICON show the Cold air in charge by midday Wednesday 16th Jan as Eastern N Atlantic UK Low drags in cold NW then Northerly air stream, but the UKMO at 144 Friday reduces the cold air by Friday- High pressure sit over UK with approaching Low from North Atlantic with another follow to its SW side.

On Friday to Sunday this morning’s 00z GFS looks cold Wednesday 16th to throughout period from then except Friday 18th as less cold, cold NW winds on Wednesday Thursday 16-17th and again for Saturday as Low Pressure exit and move to Southern North Sea Belgium Holland etc.

ECMWF unlike the 00z GFS it show UK less cold on 19th and 20th with Western SW Europe seeing SE tracking North Atlantic Low from Friday 18th.  

GFS 00z, today looks quite cold on the 21-23rd January and even colder from 24-26th January with cold NW winds turning Cyclonic then veer NE as another Deep Low from Iceland heads SE to the UK following earlier Cold NW SE moving Shortwave Low’s.

pretty good output this morning it looks cold but detail is impossible as models seem all over the place. ECM has a very cold easterly drift by day 10.