Model Output Discussion - Cold spell ending - what next?

[Eagle Eye]

24 minutes ago, joggs said:

If ne America goes cold, surely that'll just fire the jet up?.

Not really good for us coldies here imo.

Its Canada going cold that'd fire the jet up. 

[bluearmy]

7 hours ago, feb1991blizzard said:

At least there are quite a few runs lately really weakening the tropospheric vortex over Greenland, where not so long ago that wasn't the case.

perhaps a response to this.

 

I thought that but some runs are showing the upper strat slightly behind the lower strat and trop in the movement. I’d say the jury still out on whether anyone is in charge or if it’s all pretty well coupled.  Either way, the direction of travel is clear 

37 minutes ago, joggs said:

If ne America goes cold, surely that'll just fire the jet up?.

Not really good for us coldies here imo.

 

13 minutes ago, Eagle Eye said:

Its Canada going cold that'd fire the jet up. 

I just noticed the Canadian Arctic prairies 850’s forecast 30c above normal days 9/10 ! (And staying ‘warm’ across e Canada out to day 16) 

I think the northern arm strengthened in relation to the split vortex rejoining and resetting over the Asian side. Without that the jet could just as easily re Inforced the Atlantic ridge with WAA as flattened it or run underneath a block or strong wedge. that bad luck again! 

 

[MJB]

Signals continue for the PV to get beat up early March 

[Alderc 2.0]

Model output looks ideal for late winter, at least here in the south. Mild and most importantly pretty dry which appears to be a fairly unusual occurrence in recent winters. Both GFS and GEM ensembles suggest no cold until well into February with higher pressure straying not too far away from the south. 
 

[TillyS]

All 3 0z main models are zonal, with a Bartlett high. A very westerly and south-westerly Atlantic dominated pattern for now.

And Scandinavia getting pummelled by mild winds, so any colder pools are being blown away. Here are the big 3 at T240-ish (ECM, GFS) and T168 (UKMO):

 

Zonal, in a word.

[TillyS]

2 minutes ago, Alderc 2.0 said:

Model output looks ideal for late winter, at least here in the south. Mild and most importantly pretty dry which appears to be a fairly unusual occurrence in recent winters. Both GFS and GEM ensembles suggest no cold until well into February with higher pressure straying not too far away from the south. 
 

 

The issue with the hp in the south is that in the absence of any northern blocking, and a powerful flat northern jetstream, it tends to get squashed back onto the continent. A high residing over northern Germany is the worst of all possible outcomes for UK cold. Leaves us in moist south-westerlies, which is the predominant pattern now showing. As you say, the south-east ‘may’ catch a break from the high if it can hold on.

[mountain shadow]

11 minutes ago, TillyS said:

All 3 0z main models are zonal, with a Bartlett high. A very westerly and south-westerly Atlantic dominated pattern for now.

And Scandinavia getting pummelled by mild winds, so any colder pools are being blown away. Here are the big 3 at T240-ish (ECM, GFS) and T168 (UKMO):

 

Zonal, in a word.

None of those three charts show a Bartlett.

Only the first two are zonal.

[northwestsnow]

What a flippin shame

Terrible 00z output .

EC is  ghastly 

[AO-]

52 minutes ago, MJB said:

Signals continue for the PV to get beat up early March 

Good Morning 

Hope you are talking about early February. Early march would imply we write of February as well.

[Mike Poole]

ECM clusters this morning, T192-T240:

Generally a flat zonal picture, apart from clusters 3 and 5 which push a ridge up to Scandi, but it doesn’t hold and flattens again.  

T264+:

Cluster 1 (21 members) shows the Atlantic ridge scenario on which hopes for more seasonal weather depend.  The other two clusters maintain the +NAO regime.  

Just goes to show how once this +NAO zonal pattern sets in for the UK, it is hard to shift, there are, and have been, signs of change but they remain at the tail end of week 2 for now…

[AO-]

12 minutes ago, Mike Poole said:

ECM clusters this morning, T192-T240:

Generally a flat zonal picture, apart from clusters 3 and 5 which push a ridge up to Scandi, but it doesn’t hold and flattens again.  

T264+:

Cluster 1 (21 members) shows the Atlantic ridge scenario on which hopes for more seasonal weather depend.  The other two clusters maintain the +NAO regime.  

Just goes to show how once this +NAO zonal pattern sets in for the UK, it is hard to shift, there are, and have been, signs of change but they remain at the tail end of week 2 for now…

Cluster 3 isn't that bad either. The low pressure moving into Scandinavia and northwest Russia. Good precursor for cold thereafter. Also some blocking to the Northwest

Edited January 22 by AO-

[northwestsnow]

Well it's all in on  EC cluster 1 ..

As the biggest cluster we've got to hope this particular evolution grows in strength over the next few days ...

Obviously we are talking +10 day timeframe so it's aspiration at this time.

Edited January 22 by northwestsnow

[bluearmy]

25 minutes ago, AO- said:

Cluster 3 isn't that bad either. The low pressure moving into Scandinavia and northwest Russia. Good precursor for cold thereafter. Also some blocking to the Northwest

Euro heights 

losing the euro heights remains crucial - even moreso into feb 

[StretfordEnd1996]

36 minutes ago, Mike Poole said:

ECM clusters this morning, T192-T240:

Generally a flat zonal picture, apart from clusters 3 and 5 which push a ridge up to Scandi, but it doesn’t hold and flattens again.  

T264+:

Cluster 1 (21 members) shows the Atlantic ridge scenario on which hopes for more seasonal weather depend.  The other two clusters maintain the +NAO regime.  

Just goes to show how once this +NAO zonal pattern sets in for the UK, it is hard to shift, there are, and have been, signs of change but they remain at the tail end of week 2 for now…

Thanks for always posting these so promptly - saves me having to navigate through the ECMWF website to retrieve them myself (which for some reason is always a slow site to navigate around on my device!) 

In what has been a bit of a depressing set of operational runs and GFS ENS to wake up to at least these show a bit of optimism going forward. For the extended timeframe, even the clusters which don't show HP to our W/NW, even these in the majority do at least show a weakening of the euro heights, always something which helps (Edit, Bluearmy who posted about a second before I did beat me to it regarding this last point!)

 

Edited January 22 by StretfordEnd1996

[bluearmy]

15 minutes ago, northwestsnow said:

Well it's all in on  EC cluster 1 ..

As the biggest cluster we've got to hope this particular evolution grows in strength over the next few days ...

Obviously we are talking +10 day timeframe so it's aspiration at this time.

Looking through the individual stamps tells a less optimistic story.  I think this is a slow process to move the tpv away from Greenland to allow ridging to our west/northwest 

Looks like post 10 feb atm. Anything earlier would be a bonus based on what the nwp is generally showing 

[northwestsnow]

Just now, bluearmy said:

Looking through the individual stamps tells a less optimistic story.  I think this is a slow process to move the tpv away from Greenland to allow ridging to our west/northwest 

Looks like post 10 feb atm. Anything earlier would be a bonus based on what the nwp is generally showing 

Agreed , hence aspiration.

We know from the last 20 years of chasing once the TPV sets up to our NW it's the mother of all slogs to overturn. 

From an optimistic POV at least we have something to hold onto ...

[Mike Poole]

4 minutes ago, bluearmy said:

Looking through the individual stamps tells a less optimistic story.  I think this is a slow process to move the tpv away from Greenland to allow ridging to our west/northwest 

Looks like post 10 feb atm. Anything earlier would be a bonus based on what the nwp is generally showing 

It is certainly dragging its heels!  But going off the 46 it is not until w/b 12 Feb that any kind of ridging towards Greenland properly manifests itself.

Edited January 22 by Mike Poole

[sebastiaan1973]

56 minutes ago, Mike Poole said:

ECM clusters this morning, T192-T240:

Generally a flat zonal picture, apart from clusters 3 and 5 which push a ridge up to Scandi, but it doesn’t hold and flattens again.  

T264+:

Cluster 1 (21 members) shows the Atlantic ridge scenario on which hopes for more seasonal weather depend.  The other two clusters maintain the +NAO regime.  

Just goes to show how once this +NAO zonal pattern sets in for the UK, it is hard to shift, there are, and have been, signs of change but they remain at the tail end of week 2 for now…

Well it is more or less our default setting

[Rain All Night]

10 hours ago, RainAllNight said:

An overview of this afternoon's global model runs.

Deterministic runs from Mon 22nd to Sun 28th

Not the completely dry second half of the week I'd hoped for, but it doesn't look as though anything as bad as the storms of the first half of the week will reach us again.

Ensemble means from Mon 29th to Sun 4th

The south of Britain continuing to have a chance at some dry days by the looks of it. The high pressure to our south still looks like it wants to shift to the west a bit.

An overview of this morning's global model runs.

Deterministic runs from Mon 22nd to Mon 29th

It is quite frustrating seeing high pressure keep trying to come up and shield us only to be blown away again, so for that reason I rather like the last few frames of the UKMO here.

Ensemble means from Mon 29th to Mon 5th

Note the orange to the south moving west, and the purple to the north moving east.

[WeatherArc]

Most recent CFS seems to think high pressure will stick around the uk for the long run.

Possibly predicting a warmer and slightly drier spring? 

CFS now agrees with CanSIPS on above average temps in Iberia for summer, interested to see how this fits into things.

[Penrith Snow]

You have to admire the sheer size and intensity of the Bartlett on the latter stages of ECM, I estimate the Iberian High extends for 4 thousand miles from the Bay of Biscay to the Red Sea, rarely have I seen such a beast. Anyone that doubts that the sub tropical Hadley Cell has expanded needs to look at this.

Surely the MetO will change its MRF soon as I see no chance of sustained cold till late February, I think a February like 1998 (also a strong El Nino winter) is coming up and I would bet my pension on London recording 16c soon.

I am off to Southern Spain next weekend and under that colossal Bartlett I I think I will need my shorts.

Andy

[AO-]

1 hour ago, bluearmy said:

Euro heights 

losing the euro heights remains crucial - even moreso into feb 

 

True. Not great, but I see some kind of NAO neutral state as well which in turn could lead to ridging (preferably Iceland). I'm not sure if that's to be the case here. The through over the Atlantic, especially over the Azores is not really bad, I guess. 

[WeatherArc]

 

39 minutes ago, WeatherArc said:

Most recent CFS seems to think high pressure will stick around the uk for the long run.

Possibly predicting a warmer and slightly drier spring? 

CFS now agrees with CanSIPS on above average temps in Iberia for summer, interested to see how this fits into things.

Already seeing a very impressive area of high pressure to our south, just gives me more confidence to believe CanSIPS/CFS

Edited January 22 by WeatherArc

[Met4Cast]

What did previous look like a good chance of sustained high latitude blocking during February is rapidly fading. 

Despite an increasingly favourable MJO signal into the western Pacific, we’re missing a vital ingredient & that’ poleward propagating +AAM (westerly momentum). 

The arrow shows the previous “starting pistol” of +AAM anomalies propagating poleward through December & indeed into early January, this along with the MJO helped to support & sustain the recent blocking we’ve seen around the UK/over Greenland. 

Unfortunately, this time +AAM is increasingly glued to the equator & we’re not seeing this fluxing towards the pole, this helps (despite the MJO) to inflate the European ridge & indeed, a very strong signal for this within NWP through the remainder of January. A flat, mostly mild end to the month with low pressure systems deflected northwards, potentially stormy at times for Scotland. 

The reflective wave from the SSW hasn’t helped things either. So.. my hopes for something sustained in terms of cold/snow are rapidly fading. 

[feb1991blizzard]

4 minutes ago, Met4Cast said:

What did previous look like a good chance of sustained high latitude blocking during February is rapidly fading. 

 

 

The whole of feb or just the first half?

Might the AAM charts look better in 10 days time with a downstream response mid feb?.

Edited January 22 by feb1991blizzard