Too early to be sure of that, IMO. Tomorow's output will give us a better idea IMO as to whether or not it is off one one.

Like I said earlier, a few days ago the atlantic was meant to be back in control of proceedings by around the middle of the coming week, so even though it is looking likely that it will return next weekend, there is no way we can be sure of that at the moment.

Exactly David.  It was clear from the ensembles, particularly ECM, that there was doubt about what would happen.  It’s seldom wise to take the operational from one model in such situations.

It wouldn’t surprise me to see further adjustments and delays in the GFS as it’s still more progressive than UKMO and ECM.

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It’ actually six hours slower than the 12z in pushing the mild air in.

Indeed. The GFS op output continues its consistent incremental delay in the Atlantic (inevitably) moving in.

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Exactly David.  It was clear from the ensembles, particularly ECM, that there was doubt about what would happen.  It’s seldom wise to take the operational from one model in such situations.

It wouldn’t surprise me to see further adjustments and delays in the GFS as it’s still more progressive than UKMO and ECM.

Agreed, Peter.

I can still remember the extent to which some of the operational runs were all over the place in February this year, especially around the middle of the month around the time when the first indications appeared of the coming of the Beast from the East. Even normally trusted models such as GFS and ECM seems to be all at sea at one point, with both models at different times seemingly dropping the easterly in favour of the atlantic only to eventually agree on the coming of the blast from the east.

I think what happened then was that the models probably initially underestimated the strength of the block to the east and were still trying to factor in the effects of the major SSW event that month. I have read in recent days that there may well be another such event later this month, so it's still very much anyone's guess IMO as to what type of weather will dominate as we approach the festive season.

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This evening's EC 15 dayer showing that any available real cold is reserved for eastern Europe in the run up to Christmas with a fairly standard pattern over the Atlantic. Eastern Canada also looks to be unusually warm so the prospects of even some decent storminess look grim. Groundhog day continues. 

 

 

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A thing of beauty. Chart for Xmas Day.

A thing of beauty. Chart for Xmas Day.

 

Can you send me link to the above please?

Does anyone kn ow what 1hpa is like and if it's worth keeping eye on temps at that level in stratosphere?

Oranges and red's/ warmer uppers in strat do infiltrate in from Siberia into the Arctic N. Pole at end of the 18z run - this is now a consistent thing!! - if things work out 'accordingly' then watch out for January!? - SOme major changes aloft !

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ECM 12z ensemble for London

 

Now a very strong consensus across the ensemble and the Op regarding Wednesday and out to day 10. Highs on Thursday and Friday around 3-4c then a rapid climb to 13-14c on Saturday as the milder air finally pushed NE.  It’s noticeable that the GFS 12z is a mild outlier v ECM through most of this week.

The greater confidence from the Met Office would seem to reflect the tightening up of the ensemble set today.

Beyond Day 10 there’s the usual uncertainty but evidence of a shift towards average and colder options as Christmas approaches.

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GFS 0z-

The stratospheric fuel warning light has just come on with no petrol station in range

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GFS 0z-

The stratospheric fuel warning light has just come on with no petrol station in range

 

Looks good but both the BBC and Met Office not seeing any significant cold for at least a month in their forecasts. When do you think the UK will see an impact from the SSW?

 

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Looks good but both the BBC and Met Office not seeing any significant cold for at least a month in their forecasts. When do you think the UK will see an impact from the SSW?

 

As I said over on the other forum, I think a range of 30th December- 15th Jan should just about cover the period of interest as far as I'm concerned. So, a while to go. Should be some fun popping up in the modelling shortly though as the predicted SSW gets closer.

It's initiating circa day 10 at the moment.

GFSP is even more striking with the warming by the way- up to +8c. Impressive.

Toasty strat

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As I said over on the other forum, I think a range of 30th December- 15th Jan should just about cover the period of interest as far as I'm concerned. So, a while to go. Should be some fun popping up in the modelling shortly though as the predicted SSW gets closer.

It's initiating circa day 10 at the moment.

GFSP is even more striking with the warming by the way- up to +8c. Impressive.

Toasty strat

 

Thanks, hopefully the BBC and Met Office should start mentioning significant cold soon then in their monthly updates.

 

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The other thing with those stratosphere charts is just how cold it is in the vicinity of the UK - I reckon we'll be seeing these in a couple of weeks:

https://en.wikipedia.org/wiki/Polar_stratospheric_cloud

At closer range, though, ECM shows a transient snow event on Saturday as the Atlantic engages that cold air over the UK:

https://weather.us/model-charts/euro/great-britain/significant-weather/20181215-0600z.html

Quite a bit of snow "up north" from that on today's run.

GEM this morning delays the snow until Sunday, but with more undercutting going on it brings a good deal of snow across much of the UK:

http://www.meteociel.fr/modeles/geme_cartes.php?&ech=144&mode=2&carte=2

GFS, meanwhile, just shows the Atlantic ploughing through on Saturday with no leading edge snow at all. Bah, humbug!

 

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Thanks, hopefully the BBC and Met Office should start mentioning significant cold soon then in their monthly updates.

 

Im reluctant to suggest caution about Strat forecasts and their implications but an SSW, like anything that’s modelled, has to happen before it does and even if it does the effects may not be beneficial to our small segment of the planet in terms of surface cold.

Waiting game on this one IMO

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Im reluctant to suggest caution about Strat forecasts and their implications but an SSW, like anything that’s modelled, has to happen before it does and even if it does the effects may not be beneficial to our small segment of the planet in terms of surface cold.

Waiting game on this one IMO

 

I have the same concerns,  CC knows far more than me about the Strat, but the fact the Pros haven't mentioned any cold yet is a worry. 

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What I would add here is that while the models are not showing a major cold spell coming any time in the next couple of weeks, they don't appear to be indicating a mildfest either. Many runs at the moment seem to be sending the jet stream quite far south into Europe with lows passing more or less right over the UK rather than a SW-NW trajectory to the north, as quite often happens. It's a pattern that happened a few times in the first couple of months or so of last winter, IIRC.

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One thing of note with regards to the aforementioned SSW is that we’ve no guarantees that it will rearrange the deckchairs in a favourable position. It’s a ticket and we’re in the game but will our numbers come up is the question.

I'm sure there was a rise in temperature in the Stratosphere several years ago similar to what is being forecasts by the models today. Didn't that result in Greece freezing and us frying due to the setup of the HP cell?

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I'm sure there was a rise in temperature in the Stratosphere several years ago similar to what is being forecasts by the models today. Didn't that result in Greece freezing and us frying due to the setup of the HP cell?

 

Lets not forget that strat warming isnt linked to us being cold.  Its linked to changing major influences on our weather which leads to an "increased chance" of colder weather. 

 

Its easy to get carried away when its spoken about so much

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Lets not forget that strat warming isnt linked to us being cold.  Its linked to changing major influences on our weather which leads to an "increased chance" of colder weather. 

 

Its easy to get carried away when its spoken about so much

Watching Gavs breakdown of strat events the other day, and he pointed out that the near record breaking cold spell in December 2010 occurred without any strat warming at all. Surface cold in around the Arctic region was a much bigger player that month. 

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Watching Gavs breakdown of strat events the other day, and he pointed out that the near record breaking cold spell in December 2010 occurred without any strat warming at all. Surface cold in around the Arctic region was a much bigger player that month. 

Theres also been a number of SSW that have had the opposite effect and shunted us out of cold spells. There are no guarantees that we’ll benefit from any SSW event but it does increase our chance significantly which is something to hang your hat on.😁