Stratosphere Temperature Watch 2014/2015

[feb1991blizzard]

Has anyone got that link to the GEFS stratosphere temperatures please?

[bluearmy]

Has anyone got that link to the GEFS stratosphere temperatures please?

Look at p1 of the thread!

[ITSY]

I'll go into some chart detail in the MOD thread but some subtle hints of heights trying to rise towards Greenland across the GEFS suite towards the tail end of FI. Maybe downwelling effect? Arguably straw clutching but worth a peek nonetheless...

[Jamie R]

Charts don't look promising at all for the next two weeks.

This winter's beginning to look increasingly pear shaped.

 

Oh dear, I think you are missing the point! The charts are looking just how you would expect given the state of the strat, it wont be until about 2 weeks from now (possibly a little longer) when we should start to see the effects of the fairly decent warming that is forecast towards next week.

I am only a lurker in this thread but I had to say something then!

Edited January 1, 2015 by Jamie R

[bluearmy]

Berlin still AWOL so here are yesterday's 10/30/50 hpa days 8 and 10

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Edited January 1, 2015 by bluearmy

[feb1991blizzard]

Berlin still AWOL so here are yesterday's 10/30/50 hpa days 8 and 10

 

It looks to me like the warming just isn't going to get right into the core of the vortex, there is yet another warming creeping into deep FI on the GFS run right up top, there are multiple problems with that though, a) getting it into a reliable timeframe, b) the same problem as in the charts posted by you, ie - will it push the vortex sufficiently over the other side of the pole as to allow heights to build far enough North, and c) will it propagate.

[Paul123]

It looks to me like the warming just isn't going to get right into the core of the vortex, there is yet another warming creeping into deep FI on the GFS run right up top, there are multiple problems with that though, a) getting it into a reliable timeframe, b) the same problem as in the charts posted by you, ie - will it push the vortex sufficiently over the other side of the pole as to allow heights to build far enough North, and c) will it propagate.

 

The warming you mention is showing more potential every day.

 

 

Temperaturewise it looks great, but geopotentially it isn't good at all. 

 

 

At 30 hpa there is still no sign of the required zonal wind reversal within the next 10 days.

 

 

Plenty of problems, indeed, to make it a proper SSW.

 

In the meanwhile the sustained Atlantic warming may very well be going to have some easing effects on the tropospheric jet. Possibly a more southerly track, by the end of the coming week.

Edited January 1, 2015 by Paul123

[feb1991blizzard]

The warming you mention is showing more potential every day.

 

1 januari 10 hpa.PNG

 

Temperaturewise it looks great, but geopotentially it isn't good at all. 

 

1 januari geop 10 hpa.PNG

 

At 30 hpa there is still no sign of the required zonal wind reversal within the next 10 days.

 

1 januari 30 hpa.PNG

 

Plenty of problems, indeed, to make it a proper SSW.

 

In the meanwhile the sustained Atlantic warming may very well be going to have some easing effects on the tropospheric jet. Possibly a more southerly track, by the end of the coming week.

 

Yes although the warming takes it to well above average 10mb temps, if you look back to recent past, the warming events in mid winter onwards that have successfully lead to persistent blocking have tended to include the deep red colours (not far off freezing point) at 10mb over the pole, clearly wave 2 events obliterating the PV from top to bottom tend to be the best, On the subject of what constitutes an SSW that has cropped up a lot lately, of course the definition is a mean Easterly wind at 10mb at 60N, I wonder what threshold temperature wise is required to be a guarantee of this happening though (roughly), apologies if this has been answered before.

Edited January 1, 2015 by feb1991blizzard

[ItNeverSnowsInWindsor]

Afraid there's no light out of the tunnel if the GFS output is to be believed

[Paul123]

Yes although the warming takes it to well above average 10mb temps, if you look back to recent past, the warming events in mid winter onwards that have successfully lead to persistent blocking have tended to include the deep red colours (not far off freezing point) at 10mb over the pole, clearly wave 2 events obliterating the PV from top to bottom tend to be the best, On the subject of what constitutes an SSW that has cropped up a lot lately, of course the definition is a mean Easterly wind at 10mb, I wonder what threshold temperature wise is required to be a guarantee of this happening though (roughly), apologies if this has been answered before.

 

I would very much like to know it as well, what threshold is required.

 

By the way, technically spoken it seems more appropriate to me to assign a temperature criterion to any warming event, including a SSW.

Edited January 1, 2015 by Paul123

[summer blizzard]

Think we are all being a bit anal personally. The warming still looks pretty significant and I'd expect a lagged tropespheric effect even if the vortex eventually sorts itself out.

I could be wrong but I think winter 2012 saw an event that fell short but produced a first half of Feb that was extremely cold.

[NorthYorksWeather]

Think we are all being a bit anal personally. The warming still looks pretty significant and I'd expect a lagged tropespheric effect even if the vortex eventually sorts itself out.

I could be wrong but I think winter 2012 saw an event that fell short but produced a first half of Feb that was extremely cold.

 

My question is even if we don't see a technical SSW, will the strat warmings being modelled currently have enough effect on the trop in order to at least disrupt the vortex allowing at least some chance/hope of us getting a decent cold spell? Of course a full bor SSW would be ideal, however surely the current warmings will increase our chances of HLB and colder spells as we progress into January.

[summer blizzard]

My question is even if we don't see a technical SSW, will the strat warmings being modelled currently have enough effect on the trop in order to at least disrupt the vortex allowing at least some chance/hope of us getting a decent cold spell? Of course a full bor SSW would be ideal, however surely the current warmings will increase our chances of HLB and colder spells as we progress into January.

With there being a wave 2 event I suspect so. Even if it does not complete, the vortex should try to split or displace enough to produce a -AO for some time.

[bluearmy]

The real time coupling between the strat and trop vividly reflected in the 12z ECM op where the Azores high at 10/30/50 hpa displaced a bit further north than the 00z run and the same visible in the trop at the same time.

This is what supports my view that a reversal high up in the strat would have propagated quickly down. whether we get some more wave activity to split or displace the rebuilt vortex which is predicted to sit close to the pole in week 2 currently unknown by us as we await the Berlin server to be kicked (perhaps the Germans will go back to work tomorrow? Don't hold your breath though. I expect this won't be working again until Monday.)

[Catacol]

Looking for crumbs of comfort at the moment - here are a couple. I quite like these simplistic strat temperature charts: over the years they seem to have been a decent indicator of conditions aloft. Note the below average hideousness of December at both 10 and 30. But changes are occurring. Fingers crossed!

 

 

[bluearmy]

But we know they will shoot up catcol - all the modelling agrees. It's the drop back that now appears likely to follow that has led to the general tone of disappointment on here at the moment.

[chionomaniac]

But we know they will shoot up catcol - all the modelling agrees. It's the drop back that now appears likely to follow that has led to the general tone of disappointment on here at the moment.

Yes - I have always said that the JMA NP temp charts don't tell the whole story and therefore are not the best indicator of the whole NH stratospheric conditions.

Edited January 1, 2015 by chionomaniac

[bluearmy]

we finally have broad agreement between gfs and ECM on start heights at 10/30/50 hpa day 10. Whilst gfs didn't initially see the Greenland warming, ECM heights have really had to come into line with the gfs solution which it has been showing for quite a while.

And just at the time when the Berlin charts may have been really helpful in working out why, they weren't available.

[Weather-history]

Has anyone established what Chris Fawkes was on about with his tweet about SSW?

Was it mistake? Misread the charts? Saw a model we don't have an access to?

[bluearmy]

Has anyone established what Chris Fawkes was on about with his tweet about SSW?

Was it mistake? Misread the charts? Saw a model we don't have an access to?

 

he was simply referring to the upcoming split strat vortex, huge warming over greenland and into the polar area and the almost forecast reversal of zonal flow at 10hpa.  shame thats as good as it currently gets kevin.

[Weather-history]

he was simply referring to the upcoming split strat vortex, huge warming over greenland and into the polar area and the almost forecast reversal of zonal flow at 10hpa.  shame thats as good as it currently gets kevin.

Thanks.

By the sound of your response, it's not going to have much impact if at all on the troposphere.

[bluearmy]

Thanks.

By the sound of your response, it's not going to have much impact if at all on the troposphere.

Don't know kev - the way the trop/mid upper strat appears to be currently coupled, a renewed burst of wave 2 higher up might have interesting consequences down here. I wouldn't be predicting beyond the current two week zonal outlook. (Assuming that lasts two weeks)

[Nick F]

So I take it that there will be a brief split in the strat pv next week before it quickly re-organises by week 2?

[bluearmy]

So I take it that there will be a brief split in the strat pv next week before it quickly re-organises by week 2?

Just about sums it up nick - yep. How strong it will be post the split currently unknown. Would be nice to think we could get a look at a zonal flow forecast chart at some point.

[muppet]

Does anyone have a link to the precise dates (which I know are contentious) to previous SSWs?

I have a paper by Charlton Perez et al which lists 1952-2002 but nothing afterwards.

Can anyone please help? I think there have been 9 or 10 since jan 2002.

Thank you.