Model Output Discussion - Happy New Year!

[Mike Poole]

Evening folks, looks like an interesting day model wise. I've been busy travelling about so have only caught up from time to time wifi permitting.  After the dire winter so far, it seems that gradually more and more options for cold on various timescales are bubbling up, but none to the extent that they can be relied on so it is squeaky bum time as we see if we can count anything down in the remaining 6 weeks of winter.  

The first shot is obviously the northwesterly after the UK high moves into the Atlantic, but considerable uncertainty over whether this could unleash cold unstable air on the UK, or whether it would miss us east, or whether the pattern would fail to amplify sufficiently at all...all seem to be on the model output somewhere.  More runs should clear this up in the next few days.

Then what happens next, toppler?  That seems to be the presumption, but I was struck by the GEM T240:

A low over the US looks to be willing to pump up another ridge here which would prolong the interest, possibly bringing Greenland into play?

Further ahead still is the stratosphere, and I must admit given comment earlier, that I always read Cohen's blog on Tuesdays, and this week I have to say I didn't understand where he was going with it, he seemed to be suggesting the +AO regaining strength was favourite, but the models seem to be suggesting a reduction in zonal winds finally, and a warming, looking stronger on GFS 12z:

A lot of interest, but would be good to crystallise this into something in the reliable soon...

[damianslaw]

6 minutes ago, Mike Poole said:

Evening folks, looks like an interesting day model wise. I've been busy travelling about so have only caught up from time to time wifi permitting.  After the dire winter so far, it seems that gradually more and more options for cold on various timescales are bubbling up, but none to the extent that they can be relied on so it is squeaky bum time as we see if we can count anything down in the remaining 6 weeks of winter.  

The first shot is obviously the northwesterly after the UK high moves into the Atlantic, but considerable uncertainty over whether this could unleash cold unstable air on the UK, or whether it would miss us east, or whether the pattern would fail to amplify sufficiently at all...all seem to be on the model output somewhere.  More runs should clear this up in the next few days.

Then what happens next, toppler?  That seems to be the presumption, but I was struck by the GEM T240:

A low over the US looks to be willing to pump up another ridge here which would prolong the interest, possibly bringing Greenland into play?

Further ahead still is the stratosphere, and I must admit given comment earlier, that I always read Cohen's blog on Tuesdays, and this week I have to say I didn't understand where he was going with it, he seemed to be suggesting the +AO regaining strength was favourite, but the models seem to be suggesting a reduction in zonal winds finally, and a warming, looking stronger on GFS 12z:

A lot of interest, but would be good to crystallise this into something in the reliable soon...

Good to mention developments over USA, there are signs that low pressure/associated trough might position itself in a position which promotes a ridge over USA eastern seaboard, this indeed could allow heights to build over Greenland provided the PV core stays in situ N Siberia.. a possibility.. classic cold spells can suddenly occur when warm air advection takes place on west side of Greenland.

[tight isobar]

away  from everything  else yet to be deciphering. .

that's a sight to behold  alone. .

some deep frosts. ..and away from fog ladden  situ. ..some amazing  dawn/dusk  impressions  likely. .x@1045. .cell

 

 

 

edit shame it's not currently  an overhead. ..

alignment  for 1st time  in 5 years! !

Edited January 16, 2020 by tight isobar

[shaky]

3 minutes ago, tight isobar said:

away  from everything  else yet to be deciphering. .

that's a sight to behold  alone. .

some deep frosts. ..and away from fog ladden  situ. ..some amazing  dawn/dusk  impressions  likely. .x@1045. .cell

 

 

 

edit shame it's not currently  an overhead. ..

alignment  for 1st time  in 5 years! !

Yup could be some serious cold nights under that high pressure!!cold and crisp during the day as well!!perfect for some snowfall a week or so later!!

[tight isobar]

18th. .on a-retra  look again..

elongated  cell+vortex..

Greenland  a firm option! !!

[bluearmy]

Nothing doing on the ec46 beyond week 2 

[tight isobar]

2 minutes ago, bluearmy said:

Nothing doing on the ec46 beyond week 2 

tbh. .

very fickle  outs @Ec46..!!.

however,  I suppose  as stands all accounts  are on the table! ,?

[feb1991blizzard]

4 minutes ago, tight isobar said:

tbh. .

very fickle  outs @Ec46..!!.

however,  I suppose  as stands all accounts  are on the table! ,?

Week 5 anoms not absolutely tragic - not brilliant but a shift North of the anomalies would mean decent, OK the actual heights contours poor but they aint ever gonna show anything other than a W'ly on a week 5 52 member mean - that model will never show anything other than a W'ly on week 4 onwards so you have to use the clusters and spreads but we can only interpret them via the anoms.

Edited January 16, 2020 by feb1991blizzard

[nick sussex]

Cure for insomnia finally found !

GFS 18hrs run ! Zzzzzz

Absolutely mind numbing . The high gets trapped with nowhere to go as shortwave energy keeps running over the top .

By the time a clearance of that comes the ships sailed .

 

 

[tight isobar]

5 minutes ago, feb1991blizzard said:

Week 5 anoms not absolutely tragic - not brilliant but a shift North of the anomalies would mean decent, OK the actual heights contours poor but they aint ever gonna show anything other than a W'ly on a week 5 52 member mean - that model will never show anything other than a W'ly on week 4 onwards so you have to use the clusters and spreads but we can only interpret them via the anoms.

^^exactly. .

and my pay is nil on them for a while now..

the metabolism  is there in structure,  for a reverse  plume of height rises @point Greenland  point. .

however  again  I'm of confidence. .that rises and more 'supposed' in sync data. ..may have this wrongoing for placement /position  (Scandinavian  force)..and is because  of transition /upper latitude   rapid response! !!

Edited January 16, 2020 by tight isobar

[markw2680]

The lack of comments means I don’t even need to have a look at the 18z! Bit different to last night then I’d imagine

[feb1991blizzard]

Just now, tight isobar said:

^^exactly. .

and my pay is nil on them for a while now..

the metabolism  is there in structure,  for a reverse  plume of height rises @point  greeGreenland  point. .

however  again  I'm of confidence. .that rises and more 'suppised' in sync data. ..may have this wrongoing for placement /position  (Scandinavian  force)..and is because  of transition /upper latitude   rapid response! !!

Im still going for a scandi later in Feb, just squeeze what we can out of this up coming cold spell.

[feb1991blizzard]

9 minutes ago, markw2680 said:

The lack of comments means I don’t even need to have a look at the 18z! Bit different to last night then I’d imagine

Threatened a little bit but never delivered - rubbish. Lets hope its a mild outlier ths time.

Edited January 16, 2020 by feb1991blizzard

[tight isobar]

10 minutes ago, feb1991blizzard said:

Im still going for a scandi later in Feb, just squeeze what we can out of this up coming cold spell.

^^ditto. 

@Greenland  partial/- then Scandinavian  resorting. 

 

[tight isobar]

the 500  clumpers. .

have the vibe..@notion Greenland. .

then-aim trot  N-East. .

but are of immature  nature atm. 

with evolutionary  deciphering  just...GAINING. .

on those points. 

 

heights  and tropical  forcing still in incubation/lag.! !!

 

Edited January 16, 2020 by tight isobar

[MildCarlilse]

53 minutes ago, shaky said:

Yup could be some serious cold nights under that high pressure!!cold and crisp during the day as well!!perfect for some snowfall a week or so later!!

Could you define or quantify 'serious cold nights' with regard to this stage in January,current and recent synoptics, your location and in respect of the last 50 years?

[tight isobar]

4 minutes ago, MildCarlilse said:

Could you define or quantify 'serious cold nights' with regard to this stage in January,current and recent synoptics, your location and in respect of the last 50 years?

aye !!??

[SLEETY]

21 minutes ago, markw2680 said:

The lack of comments means I don’t even need to have a look at the 18z! Bit different to last night then I’d imagine

It's not too bad, still trending the right way, but everything regarding this Northerly is too far out to know what the outcome will be. Could be a really potent Northerly or nothing at all. 

Need to see if the signs of a Northerly reach the reliable time frame first,

[feb1991blizzard]

GEFS _ not as many good ones this time - if they don't recover back up on the 0z then forget a decent N'ly - that is always my method - we are mid range now - no going back - need an improvement.

[MATTWOLVES 3]

I'm not concerned by what the 18z op is showing, and certainly not what the EC46 is showing, which for me is about as useful as the CFS model... Yet again there is a fair amount of ensemble support for some quite potent cold snap/s. And I think tomorrows runs could well build on this... 

[MildCarlilse]

29 minutes ago, tight isobar said:

aye !!??

I assume then that serious cold will be overnight lows of -2c in central England,+3c over Scottish Borders and incrementally higher all points north of said. (as a southwest drift off the Atlantic will be the weather maker in these parts if charts verify)

[A Frayed Knot]

Just watched the catchup on BBC Wales weather and Derek went, cold weekend warming up again next week, so it's all tits up on here false as a WET fluff in a milk bottle, back down the garden path again, sick of this dross day in day out

[swfc]

Very little on offer this morning regarding any sign of pressure moving towards the north west.dry and a touch of frost but no sign of anything wintry of note.dry tho is one straw to clutch at I guess 

[IDO]

So despite a week of ECM "potential" D10 charts we still await that potential! Maybe today's 0z:

Looking at GEM and GFS for the same time, the ECM looks to be on its own:

Knowing how poor ECM is at that range maybe no surprise. Clearly we have to wait for models to get some coherence for post-D8 before we can write off January, but probabilities suggest, as many of us think, is that February will be the start of winter if it happens? Records suggest the US has its 3rd warmest winter on record (mid-point), and the theory that low solar activity = more blocking is looking dubious. CET of 3.9c above the average at mid-month sums it up.

Anyway the GEFS are all over the place so little point looking into FI, so until advised we should assume tPV the main driver and just hope this current intense WWB does indeed promote a true MJO signal after the lag, before it declines (GFS) in phase 7 (though other models suggest it may enter phase 8 [Australian model]). Other positive background signal and assuming the tPV starts to wind down as expected maybe a late winter still possible. Of course, the experts could be missing something and the rest of the winter may suck as well!

Edited January 17, 2020 by IDO

[feb1991blizzard]

ECM 240 not tragic but certainly not inspirational.