Hunt For Cold: Model Discussion - Heading Into Christmas

[BlackburnChris]

All I can see is that lobe of P/V moving over towards the Finland side , Which is what we need if were gonna get a Split.

[Weathizard]

Things are getting very complicated out in the Atlantic sector, for now UK high domination looks the favourite it must be said. It seems no matter what the pattern the core of the heights seems to slip back over us. Which to me makes the METO outlook even more odd they seem to make W’lies favourite, I just cannot see a prolonged period happening.

Edited January 2, 2019 by Weathizard
Wrong chart*

[Earthshine]

11 hours ago, Cymro said:

I wouldn't consider -9 dew points ‘pretty typical’ 

In the Brecon Beacons, it's not unheard of.  I was referring more to the -1C dew point across most of England.

Edited January 2, 2019 by Evening Star

[Weathizard]

Yeah the 6z turns into a bit of a bore fest in the end once again! All roads seem to lead to boredom at the moment

With such differences at day 5 though and the SSW in play im taking everything with a large spoonful of salt.

[That ECM]

With little consistency from run to run for area of the world I think it is perhaps better look at the pv profile for trends and the high over the pole is there consistently and now upto 1045. That’s a good theme and not the norm. 

[Ali1977]

1 minute ago, Weathizard said:

Yeah the 6z turns into a bit of a bore fest in the end once again! All roads seem to lead to boredom at the moment

With such differences at day 5 though and the SSW in play im taking everything with a large spoonful of salt.

The interest is 300hrs and even further into FI, SSW wise anyway 

[northwestsnow]

6Z looks more promising to me.. certainly longer term looks loaded with potential..

[Singularity]

Timing is far from clear, but it makes some sense for a brief westerly the north-westerly interlude to occur somewhere within the period 10th-14th Jan as the vortex split initially places a residual over the western N. Atlantic, and the MJO P7 + surging AAM influences won't yet have propagated across. 

 

Those first become evident as strong ridges into the Arctic from Alaska. This sets in motion a chain of events that drives a more negative NAO pattern. Meanwhile, lagged effects from the MJO P5-P6 crossing serve to increase the stratospheric split in the lower and mid-levels, moving the 'western' segment away from the N. Atlantic and across N. America.

 

GFS has been struggling as usual to sufficiently weaken the westerly flow out of N. America but the 06z has managed to have a good go at it.

[Turnedoutniceagain]

Winter's clearly over.........

 

*runs away*

[Ali1977]

7 minutes ago, northwestsnow said:

6Z looks more promising to me.. certainly longer term looks loaded with potential..

So much cold air surrounding us, when (if) the change comes we could very quickly go into the freezer - rather than have to wait a few days whilst we drag cold air in which often wastes a few days a good wind direction vs actual snow etc...

[The Eagle]

Output overnight is a little soul destroying at this stage. There is little sign of the type of northerly latitude blocking we are going to need and retrogression of our high pressure to the northwest is inhibited by the northern arm of the jet consistently.

We are depending on some dramatic signal suddenly being picked up on the models in the next few days.

I don't think many of us are expecting much to change in the outlook in the near term.

Hopefully in the medium term we might get some joy from the recent SSW event but even then there is not guaranteed to be a reaction in our favor or any reaction at all for that matter.

Still, fingers crossed.

 

 

[Methuselah]

Yabadabadooooo! I like this evolution best of all - sub-20 uppers in Scandinavia? What could possibly go wrong!

[Jason M]

25 minutes ago, Weathizard said:

Things are getting very complicated out in the Atlantic sector, for now UK high domination looks the favourite it must be said. It seems no matter what the pattern the core of the heights seems to slip back over us. Which to me makes the METO outlook even more odd they seem to make W’lies favourite, I just cannot see a prolonged period happening.

I think a period of westerlies is almost inevitable its just a matter of whether its sooner or later. Although largely rubbish the CFS run yesterday illustrated a worst case scenario where the UK high just sat there until Feb and then we went westerly anyway. I reckon it will be short lived westerly spell though so lets get it done IMHO. GFS 06Z looks very plausible to me with quick amplification thereafter and a northerly incoming.

These circular mid lat highs rarely deliver so best we are rid of it. 

 

[northwestsnow]

1 minute ago, The Eagle said:

Output overnight is a little soul destroying at this stage. There is little sign of the type of northerly latitude blocking we are going to need and retrogression of our high pressure to the northwest is inhibited by the northern arm of the jet consistently.

We are depending on some dramatic signal suddenly being picked up on the models in the next few days.

I don't think many of us are expecting much to change in the outlook in the near term.

Hopefully in the medium term we might get some joy from the recent SSW event but even then there is not guaranteed to be a reaction in our favor or any reaction at all for that matter.

Still, fingers crossed.

 

 

Thats a very fair post Eagle and pretty much sums up my thoughts if honest..

The low heights to the NW have been relentless so far, until we lose them we are in no-mans land..

6Z shows the way out of the pattern nicely as we finally see a relaxation of the systems running across the pond towards mid month..

 

[karyo]

3 minutes ago, northwestsnow said:

Thats a very fair post Eagle and pretty much sums up my thoughts if honest..

The low heights to the NW have been relentless so far, until we lose them we are in no-mans land..

6Z shows the way out of the pattern nicely as we finally see a relaxation of the systems running across the pond towards mid month..

 

I am not feeling optimistic at the moment especially after reading some posts in the stratosphere thread saying that the split is not looking favourable for the UK. Too much residual energy in the Atlantic. 

[Glacier Point]

GFS, GEFS and GGEM starting to find some consistency on the building Alaskan ridge around day 10. That allows ridge development in the North Atlantic.

Notably end of GFS (p) and op also starting to develop sub-polar lows days 12+ across the NH, suggestion of slowing zonal winds aloft.

[Stonethecrows]

A new year yet individual run tourettes as rife as ever. Still a case of one minute BOOM and talk of snowmageddon, then the next it's back to GLOOM and talk over winter over again seemingly forgetting everything else that's going on. Astonishing

[winterof79]

This is not your run of the mill warming though is it?

Its effects and duration are longer lasting than we are accustomed to. Coupled with the MJO I see no need to panic whatsoever

[tight isobar]

On 28/12/2018 at 00:20, tight isobar said:

Fair analysis...(given synops)..

Troughing...and rise pumping, and the spillage of arctic mass....

Are 'im sure' being underplayed-miss directed!.

The amping and waving is miss matching imo.

With the russian pen-being miss modeled with asian warm-to cold..cold 2 warm...due 2 ssw!..

The troughing via current data stats.. looks to angle-and drop!..

Some underplaying...and large...overplaying-looks nailed.

Via above prognosis!!

Edit various time snaps..

 

Upper disolve, clearly not factored.

As data pops-and sways with the atmospheric pushes...

Watch for the height holds of the migrating lobes(polar vortex)..

Through deciphering outs.

As both troughing...and height alingn...become alingned.

And the north-west euro quad..become the option!!

 

 

 

That pac ridge will also have gain..and aid.

Quote

The overal picture REMAINS A POSITIVE 1.

A lot of miss dynamics still at this point in time..

And given the upper atmospheric shenanigans-its further cause 4 both divergance and miss placements.

Break off vortices and pump of waa..as well as polar annoms..are bound 2 cause miss model structure..and play havoc with both synop...and most in here's nerves!!!

Im totaly confident in large alignment..and even split decipher of favour....

Keep watching!!!

 

Edited January 2, 2019 by tight isobar

[shaky]

Gfs p flatter again between 120 and 144 hours!!look forward to more boring uk high!!its never ending!!

Further south and east at 174 hours compared to 00z but way better than normal gfs!!

Edited January 2, 2019 by shaky

[frosty ground]

Probably best to to put money on Ensemble Member 4 being right!

[Methuselah]

12 minutes ago, Stonethecrows said:

A new year yet individual run tourettes as rife as ever. Still a case of one minute BOOM and talk of snowmageddon, then the next it's back to GLOOM and talk over winter over again seemingly forgetting everything else that's going on. Astonishing

I was think more along the lines of model-schizophrenia myself, STC...How can one not get a tad excited by the suggestion of sub -20C 850s, over Scandi?

Perish the thought (always assuming that the GFS hasn't been taken-over by Southern Trains!) that Snowmageddon might arrive two days' late...?

[Glacier Point]

4 minutes ago, shaky said:

Gfs p flatter again between 120 and 144 hours!!look forward to more boring uk high!!its never ending!!

.. back to views out of hotel windows in Torquay....

Unless and until upstream Pacific flow is resolved, and until strat downwelling takes place, out to day 10 will have a strong mid latitude high component for NW Europe.

[Ali1977]

Still a few good looking GEFS out there.

[frosty ground]

GFSP looks like its heading in the right direction

A lot of the ensembles transfer low height into Europe