Model output discussion - The Hunt For Cold

[feb1991blizzard]

ECM eps must include a reasonably sized cluster that supports the 3 pronged attack.

[Mike Poole]

1 hour ago, ICE COLD said:

It's just seems amazing over the last 7 or 8 months how the models have forecast a breakdown to a long spell off zonal weather and then back tracked to more high pressure domination . 

Yes 2018!  Some thoughts from models viewed and what I've read recently, might help or confuse! Something major about our weather changed after the massive SSW in February.  And while the SSW was the corner stone to it, it is implausible that it's effects are still being felt, I think.  What might still be being felt is the myriad influences that caused that massive SSW, but they are harder to understand.  

There are a number of factors in our favour at the moment which may or may not be relevant to the current and forecast disturbed trop vortex:

- solar activity, nearing solar minimum, evidence suggests more meridional jet.

- QBO, still easterly at 30-50 mbar level - but not for long.  This will turn against us later. 

- ENSO, likelihood of Modoki  (Central pacific) Moderate El Niño, which favours cold weather here compared to the East Pacific variety - hasn't really got going yet though. 

- Rapid advance in snow cover in last week, should favour weakened PV later.

- Sea ice - real wild card this one,  much reduced in some areas, no idea how this will play out.

I would still rate early winter cold for the UK as a better than evens chance.  I also still think late winter (Feb) could be mild.  

Nearer term, ECM ensemble mean lends support to the dismembered vortex outcomes of various of the op runs at T240:

Or - the less scientific approach - maybe just something changed this year, and winter will be different to usual just like the other three seasons were.  Hope so...

Edited October 30, 2018 by Mike Poole

[damianslaw]

Models showing a stalemate holding patter, with heights building through Europe holding the atlantic trough to our west, and enabling significant warm air advection to penetrate into the pole through central europe, a notably warm start to November over on the continent, these are good building blocks for a very rapid transition to a colder blocked continental theme, with the trough backing west and disrupting and heights joining forces with building heights over the Pole, hence a switch to an easterly and retrogression of heights can quickly occur thereafter.

I can take 10 days of mild atlantic gunk if it is quickly followed by a much colder drier continental theme and later on a polar blast.

[SMU]

GFS 18z better amplified through 96 should formulate a better scandi block day 10...

[northwestsnow]

Looks to me like GFS is following EC here- suspect the odds are beginning to shorten on the block winning out now medium term, would love to see a continental cool down for mid November.

[feb1991blizzard]

Yes, this is going to be a stonker. There could be a real continental freeze down never mind cool down by the end of this run, how far west im not sure of.

Edited October 30, 2018 by feb1991blizzard

[ICE COLD]

Wow it's getting there 

[JeffC]

1 hour ago, damianslaw said:

I can take 10 days of mild atlantic gunk if it is quickly followed by a much colder drier continental theme and later on a polar blast.

but please not like 2009!

[ICE COLD]

The cold air gradually coming round the back door 

[ICE COLD]

That is one big block . Something is brewing my cold hunters .

[feb1991blizzard]

3 minutes ago, JeffC said:

but please not like 2009!

Dont care how as long as we get there!

 

1 minute ago, ICE COLD said:

That is one big block . Something is brewing my cold hunters .

Yes, although we have had these type of setups in early season only for the strat PV VI to downwell towards mid season and do it very very quickly, i just wonder if thats do do with climate these days, that the late period of VI means any early E'ly doesnt deliver and then the breakdown of the PV occurs later, just wondering if Nov is the new Oct Feb the new Jan and March the new Feb etc, there are warning signs IMO the last few years - just one to throw in there.

[SMU]

More ENS coming aboard

PTB 3 & 15 !!negative til 168 - 192 like the ECM could be a belter...

Edited October 30, 2018 by Steve Murr

[ICE COLD]

9 minutes ago, feb1991blizzard said:

Dont care how as long as we get there!

 

Yes, although we have had these type of setups in early season only for the strat PV VI to downwell towards mid season and do it very very quickly, i just wonder if thats do do with climate these days, that the late period of VI means any early E'ly doesnt deliver and then the breakdown of the PV occurs later, just wondering if Nov is the new Oct Feb the new Jan and March the new Feb etc, there are warning signs IMO the last few years - just one to throw in there.

Yer that's the only worry . Hope we don't see all these nice setups just disappear and not return until late Feb . Be nice for once to have a cold December especially Christmas week and a cold Jan . The next few weeks will tell . 

[feb1991blizzard]

Another slightly better GEFS suite so far, slightly further west and sharper on the mean.

[feb1991blizzard]

4 minutes ago, phil nw. said:

The current eastern block though can flatter to deceive as it is unlikely to get cold from the east with this sort of alignment of the main players especially with the Atlantic trough fairly close by pushing those south westerlies in.

True but with these sharp ridges attacking the PV and stopping the strat vortex from being the dominant player, its still better than SWerlys straight through Norway and Sweden and into Russia.

[northwestsnow]

Just now, feb1991blizzard said:

Another slightly better GEFS suite so far, slightly further west and sharper on the mean.

Yes the model has now realized the Atlantic is not going to roll this block over,I'd expect the meto update tomorrow to put a little more stock in the High pressure building to the ENE direction - promoting a continental feed.

Really happy with the notion of a mid November Euro cooldown..

[feb1991blizzard]

Some mouth watering ens - i love these ttypes of setups i do - these are the ones that have a chance of ending up with record breaking upper cold pooling as the fetch of air into the continent can be so long in the end.

EDIT : and right on cue - would surely be a jan 87 if it went 72 hours further

Or a Feb / March 18 of course!

Edited October 30, 2018 by feb1991blizzard

[feb1991blizzard]

A mean surface E'ly (although not cold upper wise) at 384!

Edited October 30, 2018 by feb1991blizzard

[Kirkcaldy Weather]

Two words to some up the 18z GEFS -  NORTHERN BLOCKING

           

[JeffC]

9 hours ago, feb1991blizzard said:

Dont care how as long as we get there!

From a meteorological perspective I would agree, I just hope that the Lake District is spared the worst of the rain. Many flood defences haven't been completed and given the result of 2009 and then Desmond, it is a concern. 

Hopefully the models will firm up and at least give everyone the heads up to allow preparation for events. 

[MR EXTREMES]

I'd be very careful on easterly not always successful.

Northern blocking is there but I've seen at 72hrs the whole pattern collapse into a Prozac moment.

But there is more interest this year but I'd be reluctant to shout game on.

For now anyway.

[Newberryone]

Any eastern block not quite as evident with the atlantic still looking very dominant as we progress through next week. Looks like as always western areas seeing the highest precipitation with embedded troughs in the flow. Even at day ten the atlantic seems to be met with little resistance from the east. Any low pressure systems admittedly by then look far less menacing in nature.

[tight isobar]

20 minutes ago, Newberryone said:

Any eastern block not quite as evident with the atlantic still looking very dominant as we progress through next week. Looks like as always western areas seeing the highest precipitation with embedded troughs in the flow. Even at day ten the atlantic seems to be met with little resistance from the east. Any low pressure systems admittedly by then look far less menacing in nature.

Like-or loathe...its that atlantic energy formats...in the trough/troughs...that will further aid-advancing WAA into large scale eastern euro/scandinavia...then more deeply into the pole as we gain.

Bringing more favourable synops-later into november....

That all without the mention of other parameters at 'certain geographical points'-@northern hem.

Its a very good all round evolving pattern....and at the correct time placements...

Cross ensembles will be of upmost decipher as the above mentioned begins the play-out process !!!

Id expect a strong signal of this even in mid term ens rather soon...with a note of decline.....

Edited October 31, 2018 by tight isobar

[weirpig]

Eastern Block still holding firm  with depressions in the Atlantic being driven North.  Then later in the run  High still present  with Atlantic lows diving on a more southerly route.  Still nothing of note  for cold lovers.  Of course still very early.  

[Guest Delete Me]

Looks great at T+384!

Short term rain, long term gain....hopefully!