Model Output Discussion - Colder but how cold and for how long?

[TillyS]

14 minutes ago, KTtom said:

As mentioned above, UKMO slaps a nasty storm smack over the UK next weekend! Damaging winds in the south IF it were to verify like this..the other thing that jumps out at you with this chart is just how flat the pattern is..

Thanks for the heads-up KTtom, and previous kind comments. That is indeed wild. The fact that it’s UKMO means it won’t be dismissed out of hand.

 

As you and others have mentioned, there’s a large high pressure to the south of the UK showing up on all the models. With an Iberian high like that - see your chart - and a powerful flat jet, the mild would likely set-in for a while. 

Edited January 15 by TillyS

[joggs]

30 minutes ago, KTtom said:

As mentioned above, UKMO slaps a nasty storm smack over the UK next weekend! Damaging winds in the south IF it were to verify like this..the other thing that jumps out at you with this chart is just how flat the pattern is..

Yes,could develop into a nasty little storm that. Poor charts for cold all the way through from all models. Can't we just nuke them Iberian heights

[KTtom]

The other startling observation looking through this mornings models is how quick a south westerly flow can blow away the cold over Scandinavia... Ive a vested interest in Kuusamo weather in Finland, its been hovering about -20 since before xmas.. a 20 c rise expected in a weeks time.

[Gowon]

A glimmer of hope at the end of ECM:

A wedge of heights to hopefully derail the powerful jet.

[IDO]

There is no sign on the GEFS mean yet of a quantifiable change concerning the UK returning to cold by D16. Taking the last cold spell and the subsequent 3-4 weeks of changeable weather, it may be too early to show up. The GEM and GEFS D8-16 mean:

 

Very similar NH profiles. It does appear the upcoming pattern is of relatively high confidence. The tPV returns to our NW by D16 with a nascent Pacific ridge. Neither suggests an Atlantic ridge is viable in that period or the immediate days post-D16.

The usual caveats, of course, but maybe in week two of February before we see another shot based on current means. Before then a cold zonal flush followed by a weaker zonal regime with maybe the south less wet.

 

[Vikos]

My confidence rises that this mild spell isn’t going to be as long as the models predict… next chase starts around 26/27th

 

Edited January 15 by Vikos

[Nick2373]

00z looks like we will have a milder windy conditions for 3 maybe four days then we see height raises around the 25th, where some are getting mild setting in for a while I'm not sure.  the picture i.e trend seems to be pointing towards something more pleasant and dryer again after this little blip, i think with the high pressure setting up once again we'll see a decrease in terms of temps closer to the date i should imaging hovering around the 30 year mean. Mild Wet Windy yes for a few days then high pressure setting up shop again from the 25th onward 

[SLEETY]

Woeful outlook if your interested in cold and snow after this week, and the chance of snow in the far South mid-week, has gone, virtually every model has the low too far South.

Why is anyone surprised any more. 

[Nick2373]

1 minute ago, Vikos said:

My confidence that this mild spell isn’t going to be as long as the models predict… next chase starts around 26/27th

Agree the trend seems to be popping up on each run ties in with the post i placed above, something dryer from the 25th onward temps to be decided but should imagining given where i think the high will set up could be looking at possibly North East or Eastly direction 

[John88B]

7 minutes ago, Nick2373 said:

Agree the trend seems to be popping up on each run ties in with the post i placed above, something dryer from the 25th onward temps to be decided but should imagining given where i think the high will set up could be looking at possibly North East or Eastly direction 

Yes Nick and more importantly it ties in with the met office outlook for late January into early February. I have a feeling this winter is far from over!

[sunnijim]

1 minute ago, SLEETY said:

Woeful outlook if your interested in cold and snow after this week, and the chance of snow in the far South mid-week, has gone, virtually every model has the low too far South.

Why is anyone surprised any more. 

The ooz gfs was actually an upgrade of sorts for snow compared to the two previous runs.

All semantics now I guess.

I was  wondering if the SSW  might be responsible for the rapid change to mild and possible Bartlett.....

Any research done  on  this?  if a Northern block is in place when the effects of a SSW trickle down, what can happen to the block and can it lead to an unpalatable outcome as we see lined up next week?

I seem to have read that our current block was not the result of the mild SSW..

[TillyS]

13 minutes ago, Nick2373 said:

00z looks like we will have a milder windy conditions for 3 maybe four days then we see height raises around the 25th, where some are getting mild setting in for a while I'm not sure.  the picture i.e trend seems to be pointing towards something more pleasant and dryer again after this little blip, i think with the high pressure setting up once again we'll see a decrease in terms of temps closer to the date i should imaging hovering around the 30 year mean. Mild Wet Windy yes for a few days then high pressure setting up shop again from the 25th onward 

 

The models do not support it as “a little blip”. There’s high pressure to the south of the UK and zonal conditions on all 3 main models. Potential height rise looks transient or, worse, a high over Benelux-Germany. That way lies disaster for UK cold.

I get it that people want to see cold, snowy, conditions but there’s no point telling ourselves something is there when it isn’t really evidentially supported by the models.

Enjoy the cold this week and make the most of it. It’s heading mild after that for the time being.

6 minutes ago, sunnijim said:

 

I was  wondering if the SSW  might be responsible for the rapid change to mild and possible Bartlett.....

 

It's certainly responsible for wishful thinking  

[SLEETY]

Remember spring a couple of years ago when the Greenland high dominated for the whole month, think May? I know the vortex is weaker in Spring  then Winter but still struggling to see how this Greenland high just seems to vanish in 24 hours. 

Can't withstand the onslaught of the low and it's game over. 

Struggling to see any way back to cold from here. 

 

[Vikos]

A lot of moaining going on here. Why? Just because this mild interlude? Some will rub their eyes… no confidence in cold spells but mild is rock solid carved in stone? 

[TillyS]

2 minutes ago, SLEETY said:

Remember spring a couple of years ago when the Greenland high dominated for the whole month, think May? I know the vortex is weaker in Spring  then Winter but still struggling to see how this Greenland high just seems to vanish in 24 hours. 

Can't withstand the onslaught of the low and it's game over. 

Struggling to see any way back to cold from here. 

 

Whilst this may be going slightly far it’s certainly the case that the outlook next week on the models is for mild Atlantic-dominated weather.

I’m sure we can find esoteric ensemble members, obscure minor models, or tea leaves to suggest otherwise but them’s the current facts.

There’s still a lot of time. February and March can be cold or very cold, but the final third of January looks set in for mild.

[SLEETY]

Just now, Vikos said:

A lot of moaining going on here. Why? Just because this mild interlude? Some will rub their eyes… no confidence in cold spells but mild is rock solid carved in stone? 

In UK yes when mild takes control it can last for weeks and cold rarely survives more than a week. 

Just the way it is but the northwards shift of the Azores high in winter has made cold even harder to achieve 

[TillyS]

2 minutes ago, SLEETY said:

In UK yes when mild takes control it can last for weeks and cold rarely survives more than a week. 

Just the way it is but the northwards shift of the Azores high in winter has made cold even harder to achieve 

I often see people saying that if you lean towards likelihood of mild you aren’t being balanced and why should we think cold is any less likely than mild. However, the fact is that the UK is tilted mild, geographically, meteorologically, and oceanically. That is only now compounded, as you say, by climate change drivers: the biggest teleconnection of them all but the one which is routinely left out of the analysis.

If when we watch the models we started with a presumption of doubt we’d be more accurate. The question: what can go wrong probably will is about right for UK winter weather. 19 times out of 20 these days any snowy set up showing on the models out past T168 will not happen.

[AO-]

20 minutes ago, sunnijim said:

The ooz gfs was actually an upgrade of sorts for snow compared to the two previous runs.

All semantics now I guess.

I was  wondering if the SSW  might be responsible for the rapid change to mild and possible Bartlett.....

Any research done  on  this?  if a Northern block is in place when the effects of a SSW trickle down, what can happen to the block and can it lead to an unpalatable outcome as we see lined up next week?

I seem to have read that our current block was not the result of the mild SSW..

Goed morning

My best guess would be the reinstalling (shortlived or not) of the vortex. The part over Canada is moving east faster than initially calculated. The fire up of the vortex takes only a few days. The past has shown that in colder winters the zonal spells can be short but possibly only with a cold history(?). The next Chase begins at day 10 when EC is showing a wedge, which is too far east atm. The support in the EPS shows that the operational is not alone. But winter is far away from the 22nd onwards. 

[That ECM]

3 minutes ago, TillyS said:

If when we watch the models we started with a presumption of doubt we’d be more accurate. The question: what can go wrong probably will is about right for UK winter weather. 19 times out of 20 these days any snowy set up showing on the models out past T168 will not happen.

Currently in the 1 in 20 right now then. 
 

is the detail as was suggested past T168? No. Is this a snowy set up that was shown prior to T168? Yep.

 

[Nick2373]

28 minutes ago, TillyS said:

 

The models do not support it as “a little blip”. There’s high pressure to the south of the UK and zonal conditions on all 3 main models. Potential height rise looks transient or, worse, a high over Benelux-Germany. That way lies disaster for UK cold.

I get it that people want to see cold, snowy, conditions but there’s no point telling ourselves something is there when it isn’t really evidentially supported by the models.

Enjoy the cold this week and make the most of it. It’s heading mild after that for the time being.

It's certainly responsible for wishful thinking  

??? Time will tell i suppose the trend for something wetter windy as been model in the gefs for days which shows from the 21st onward to the 25th its four days not weeks i stand by what i said I've been seeing on the gefs a lot of people knock it but if and it pretty good at picking up trends/patterns. Zonal no transient yes to something dryer and given that anything past 5 days can sometimes be classed in the realm of FI the models may not always be spot on the money.  

Edited January 15 by Nick2373

[sunnijim]

4 minutes ago, AO- said:

Goed morning

My best guess would be the reinstalling (shortlived or not) of the vortex. The part over Canada is moving east faster than initially calculated. The fire up of the vortex takes only a few days. The past has shown that in colder winters the zonal spells can be short but possibly only with a cold history(?). The next Chase begins at day 10 when EC is showing a wedge, which is too far east atm. The support in the EPS shows that the operational is not alone. But winter is far away from the 22nd onwards. 

Thanks for this, glad someone with some knowledge was able to come up with a conclusion to a question that might seem daft on the face of itWe assume that the strat warming can lead to Blocking, but if the block is already in place before the lag effects hit, can it set up a block in the wrong place and wipe out the 'good' we have now.?

[northwestsnow]

Such a shame the south look like JUST missing out

Hopefully some further North into Cumbria NI and Scotland hit the jackpot over the next 48 hours ..

NWP looks awful after Thurs, we need the PV to go and get a life away from Greenland.

[AO-]

5 minutes ago, sunnijim said:

Thanks for this, glad someone with some knowledge was able to come up with a conclusion to a question that might seem daft on the face of itWe assume that the strat warming can lead to Blocking, but if the block is already in place before the lag effects hit, can it set up a block in the wrong place and wipe out the 'good' we have now.?

Wel in my humble opinion it would reinforce a hlb rather than sweep it to an unfavourable place. In the worst case the block occurs in the wrong place for us with us being on the upgoing side of the pattern, being a southerly rather than a northerly current.

[nick sussex]

3 minutes ago, northwestsnow said:

Such a shame the south look like JUST missing out

Hopefully some further North into Cumbria NI and Scotland hit the jackpot over the next 48 hours ..

NWP looks awful after Thurs, we need the PV to go and get a life away from Greenland.

There’s still some uncertainty there , also as the front might pivot as the low tracks east so some precip could edge nw into the far se as that happens .

It is very frustrating as the snow could have lasted a while .

I’d give it till the end of today .

 

[sunnijim]

2 minutes ago, northwestsnow said:

Such a shame the south look like JUST missing out

Hopefully some further North into Cumbria NI and Scotland hit the jackpot over the next 48 hours ..

NWP looks awful after Thurs, we need the PV to go and get a life away from Greenland.

Reasons to be slightly optimistic this morning.

Granted it is the equivalent of expecting rib eye steak and being served the possibility of a spam fritter ( apologies to veggies )

Latest Exeter thoughts show the front 50 miles further North than the fax yesterday and the front dropping down the UK exiting via the Wash rather than the South coast, this may help the Low over France track toward us at the same time, and a Northward nudge on the latest GFS.

It has to be said a major surprise now would be getting precipitation to London( although not beyond the relms in these set ups) and more likely some light snow ( 40% chance) for coastal parts) the mild sector needs holding back, so hoping for more would lead to disaster anyway with cold rain.