Hunt For Cold: Model Discussion - Heading Into Christmas

[ALL ABOARD]

2 minutes ago, mountain shadow said:

BECAUSE THE IMPACT OF THE SSW ON THE TROPOSPHERE IS CURRENTLY OUTSIDE OF THE RANGE OF THE TROPOSPHERE MODEL OUTPUT.

 

He's talking about the GFS OP with regards to reversal in the Strat.

[karyo]

In recent days the 6z was the most enthusiastic of the gfs runs re: strato split. Not today though, the 6z has also backed down from the ideal split scenario.

[northwestsnow]

2 minutes ago, karyo said:

In recent days the 6z was the most enthusiastic of the gfs runs re: strato split. Not today though, the 6z has also backed down from the ideal split scenario.

Clearly EC and GFS not on the same page K, lets hope EC is closer to reality -

 

[booferking]

Honestly guys stop looking miles ahead and look whats possible in 6 days time 6z 138hr..

Edited December 20, 2018 by booferking

[Met4Cast]

Time for a bit of positivity, perhaps? The EPS is fairly solid with a strong signal for high pressure to be over the UK through the Christmas period and into the New Year

Extended EPS this shifts that high back out into the Atlantic, though not particular far North it's an encouraging signal to see

[Snowy L]

13 minutes ago, northwestsnow said:

Again, thanks for this Sebastiaan , EC still going for a split, GFS not so keen..

The plot thickens ..

 

That's a superficial split, follow the isobars outside the lobes, the two lobes are still encased in one polar vortex that the High pressure has failed to cut through. It is also suffering from the same problem as the GFS in that there is zero pressure on the vortex from our side of the North Pole. The vortex will recover from that.

For reference this is a real vortex split

Two completely separate lobes with no isobars linking them.

[sebastiaan1973]

Well. It's too early for such a split.

[feb1991blizzard]

26 minutes ago, blizzard81 said:

Even the comments in the strat thread are a bit more downbeat this morning. 

Nothings really changed though, disagreement, EPS mean shows a favourable split, not enough distance in between vortices but that could be because its only at the end of the range, if it goes out further, the split might be wider, + its an ensemble mean so it will grow stronger if its on the right track, the problem at the moment is we can't get GFS / GEFS support for the EPS / ECM op strat evolution. in fact the GFS op is now showing sighns of a split but in an unfavourable location can you believe it!!

https://www.instantweathermaps.com/GFS-php/strat.php?run=2018122006&var=HGT&lev=10mb&hour=384

Edited December 20, 2018 by feb1991blizzard

[Team Jo]

54 minutes ago, feb1991blizzard said:

Yes, people who are writing off the January spell are premature and very possibly wrong, however, discussing the Strat warming is massively relevant, moderators saying just wait for the timescale to come into range of the models are missing the point, the strat output is vital determining this, if the 1mb chart on the ECM i posted earlier comes to fruition and is repeated at 10mb, then yes, its practically inevitable we will have a bitter Jan spell, but i have never seen such variation from modelling of the strat at such short timescales before, until we get agreement on the specifics of the SSW in terms of where the daughter vortices end up then it is perfectly valid for discussion.

I'm not missing the point Feb, sorry if I wasn't clear.  The point I'm making is that people looking for cold/easterly output in the reliable (and there's an awful lot of them on the last 6 pages...) that may arise from an SSW need to be patient.  I wasn't referencing the strat output.

 

 

[Methuselah]

I'll be interested to see the MetO's interpretation of the latest signals: MOGREPS and GLOSEA will no doubt provide their own respective perspectives...?

[feb1991blizzard]

1 minute ago, Team Jo said:

I'm not missing the point Feb, sorry if I wasn't clear.  The point I'm making is that people looking for cold/easterly output in the reliable (and there's an awful lot of them on the last 6 pages...) that may arise from an SSW need to be patient.  I wasn't referencing the strat output.

 

 

Ok - sorry, maybe i missed the point then!    but  Nick Sussex's post is a perfectly acceptable post though, he is just saying the trop output is poor and we are reliant on an SSW, he isn't saying it wont improve - just that its poor for cold over the next 15 days. Now some (not saying you) would criticise it for being negative but i suggest its just saying what the model suggests.

[blizzard81]

On a more positive note, the gfs para is an improvement at quite short range. Time for this model to start proving itself now though. 

[weirpig]

Maybe clutching at straws here  but the Para  is much more amplified  on the 6z

 

[frosty ground]

7 minutes ago, feb1991blizzard said:

Nothings really changed though, disagreement, EPS mean shows a favourable split, not enough distance in between vortices but that could be because its only at the end of the range, if it goes out further, the split might be wider, + its an ensemble mean so it will grow stronger if its on the right track, the problem at the moment is we can't get GFS / GEFS support for the EPS / ECM op strat evolution. in fact the GFS op is now showing sighns of a split but in an unfavourable location can you believe it!!

https://www.instantweathermaps.com/GFS-php/strat.php?run=2018122006&var=HGT&lev=10mb&hour=384

Yes because 33% of the time it is unfavourable 

Edited December 20, 2018 by frosty ground

[johnholmes]

8 minutes ago, Snowy L said:

That's a superficial split, follow the isobars outside the lobes, the two lobes are still encased in one polar vortex that the High pressure has failed to cut through. It is also suffering from the same problem as the GFS in that there is zero pressure on the vortex from our side of the North Pole. The vortex will recover from that.

For reference this is a real vortex split

Two completely separate lobes with no isobars linking them.

Being a bit pedantic but I suspect not the only one using the 'lines' and calling them isobars. They are not isobars but contour lines at the 10 mb level. There is a distinction between isobars and contours honestly. 

[Singularity]

This is crazy from GEFS. Seems to be way over the top with the effect of the MJO moving through Indonesia and temporarily working against the Nino standing wave (the wave form that we need for poleward ridging and extra wave-2 into the stratosphere). It's the usual negative bias gone into overdrive!

No surprise to see it being so westerly-orientated week 2 onward. ECM doesn't seem to be faring much better at the mo but the EPS majority vote looks alright.

Just to clarify, mind - there's still going to be enough interference to prevent high latitude ridges bringing major cold conditions to our shores pre-SSW impacts; I'm just expecting the ridges to be less flat; persistent mid-latitude ridges, probably over the UK as per EPS, with cold surface conditions achievable at least by night.

[blizzard81]

All this anti-negative tosh really does my head in to be honest. 'stop being negative' 'the negative nellie's are back' etc, etc. People are just posting what they see - just let them be and allow them to express themselves, even if it isn't what you want to hear. By all means offer counter arguments if you disagree but just responding with the 'negative' insults is just down right silly and immature imo. 

[swfc]

3 minutes ago, blizzard81 said:

All this anti-negative tosh really does my head in to be honest. 'stop being negative' 'the negative nellie's are back' etc, etc. People are just posting what they see - just let them be and allow them to express themselves, even if it isn't what you want to hear. By all means offer counter arguments if you disagree but just responding with the 'negative' insults is just down right silly and immature imo. 

Good point tbh,commenting on poor output isn't a bad thing if its whats on the mo.Talking about what mighnt or could happen in 14-20 days is possibly like calling the lottery numbers imo .Hopefully winter delivers six numbers in the near future

Edited December 20, 2018 by swfc

[sebastiaan1973]

7 minutes ago, Singularity said:

 

This is crazy from GEFS. Seems to be way over the top with the effect of the MJO moving through Indonesia and temporarily working against the Nino standing wave (the wave form that we need for poleward ridging and extra wave-2 into the stratosphere). It's the usual negative bias gone into overdrive! No surprise to see it being so westerly-orientated week 2 onward. ECM doesn't seem to be faring much better at the mo but the EPS majority vote looks alright. 
Just to clarify, mind - there's still going to be enough interference to prevent high latitude ridges bringing major cold conditions to our shores pre-SSW impacts; I'm just expecting the ridges to be less flat; persistent mid-latitude ridges, probably over the UK as per EPS, with cold surface conditions achievable at least by night.

Thanks. Such insights helps us further. 

[MattStoke]

2 hours ago, Purga said:

Well it appears that the initial Trop response is:

 

You've got to have a sense of humour though it's Christmas! .

 

Very much doubt we’re seeing the trop response in the model output. It’s too early.

[frosty ground]

Just need that kink in the Jet over Scandi to back west and break!

[weirpig]

Well the Para  is better  Cold in Europe much further west  cold a frosty nights as we approach the new year   quite a difference in the profile at such a range. 

[blizzard81]

2 minutes ago, weirpig said:

Well the Para  is better  Cold in Europe much further west  cold a frosty nights as we approach the new year   quite a difference in the profile at such a range. 

Much better run for our neck of the woods. Need to see this built upon on the 12z runs. 

[booferking]

16 minutes ago, Singularity said:

This is crazy from GEFS. Seems to be way over the top with the effect of the MJO moving through Indonesia and temporarily working against the Nino standing wave (the wave form that we need for poleward ridging and extra wave-2 into the stratosphere). It's the usual negative bias gone into overdrive!

No surprise to see it being so westerly-orientated week 2 onward. ECM doesn't seem to be faring much better at the mo but the EPS majority vote looks alright.

Just to clarify, mind - there's still going to be enough interference to prevent high latitude ridges bringing major cold conditions to our shores pre-SSW impacts; I'm just expecting the ridges to be less flat; persistent mid-latitude ridges, probably over the UK as per EPS, with cold surface conditions achievable at least by night.

Something like this..

[weirpig]

To compare  240hrs  0z 6z     Lol  Para  going for it in low res  going full on scandi mode

Edited December 20, 2018 by weirpig