Stratosphere Temperature Watch 2014/2015

[Duane S.]

That sounds good IF it has a positive effect?  Just that there were good signs weeks ago too.  Like I say not writing off Jan just whether the strat warmings are positively effecting / or will in near future.  Up til now that PV has ridden the knocks to survive pretty well 

 

regards

 

BFTP

Agreed, it may not have go our way but the chances are it will greatly open up the window of opportunity at least. In fact I've just had a perusal of the latest top strat temp charts, and this has got to be the strongest warming seen to date...

 

>44 degrees!!

 

The good news (if it were to verify of course), after a sustaned 2 week warming in the upper echelons of the strat, this would likely decimate it!

[snowking]

GEFS mean panels show nicely the continued nature of the warmings at 10mb:

 

 

With an ensemble mean producing this sort of outlook anybody even hinting at writing off an interesting January stratospherically is rather foolish at this stage.

 

We can see that at this particular height much of the warming is Wave 1 led - largely owing to the huge Aleutian low which has re-rstablished itself:

 

 

We can also add the NAEFS ensemble mean in to this arena too:

 

 

Of course whilst we can roll the dice and pray for something decent following a Wave 1 attack, ultimately the favoured solution is always going to be a Wave 2(+) attack, and we see some subtle hints at this from ECMWF ensemble means posted via WSI in recent days, and indeed from yesterdays 12z det:

 

 

Even without it, notice the huge drop in mean zonal winds at 1mb, and how this is slowly downwelling to 10mb by this stage too:

 

 

All of this makes for one very unhappy vortex, and we are starting to see some effects from this a bit lower down too as this destabilising takes place above concurrently:

 

 

I guess if I were to sum all of this up in one meme:

 

 

SK

 

[karyo]

The 6z had a good weakening of the vortex and eventual split around the 300 hour mark while the 12z couldn't be more different with the vortex staying in one piece and strengthening in the end. I know there is supposed to be some variability in FI but this is too much.

 

By the way, I am talking about the 30hpa level.

 

Karyo

Edited December 21, 2014 by karyo

[Snowman.]

The 6z had a good weakening of the vortex and eventual split around the 300 hour mark while the 12z couldn't be more different with the vortex staying in one piece and strengthening in the end. I know there is supposed to be some variability in FI but this is too much.

 

By the way, I am talking about the 30hpa level.

 

Karyo

 

Very hard to make a call Karyo.

 

Some of the folk in the model thread don't seem to realise how unpredictable the models are going to get.

 

What we do know is Wave 1 and possibly wave 2 attacks are continuous along with the warming at 1mb showing no signs of stopping we should take each day in it's stride and not to think to hard about the what the future may hold. 

[Interitus]

 

We can see that at this particular height much of the warming is Wave 1 led - largely owing to the huge Aleutian low which has re-rstablished itself:

 

 

Aleutian high 

[bluearmy]

Aleutian high 

 

i think its a n pacific low which has re established in the area. now whether its this feature which has been the driver for the activity at the top of the strat ????

[lorenzo]

Aleutian High - going polar. Also Aleutian low a vital stratospheric starter pistol. SK knows what he means.. 

[snowking]

Aleutian high 

Yes sorry badly worded - tropospheric low

[bluearmy]

Pedantry apart, the Berlin charts this morning are decent. Tick off the forecast of a reversal at the very top over the pole. now just got to get it to T0. A zonal flow worth it's name north of our lattitude virtually non existent by day 10. wave 2, whilst not being strong is evident to quite low levels though whether that will be enough to split a displaced vortex is questionable. wave 1 remains strong.

What is also noticeable is the momentum flux and temp flux charts seem quite 'flaccid'. Normally, these contain areas of low flux and high flux with marked boundarys - presumably preventing waves from progressing easily. just seems that a very relaxed environment is predicted by day 10. If the strat is not going to down well any particular pattern to the trop, then it's just down to the trop to do whatever it wants to. that's why a stronger wave 2 would be appreciated?

Of course, that last para could be 'tosh' but there is something very different to normal conditions for this time of year.

And those temps are on the rise in the graph (as expected). Always nice to see it on a familiar template.

[Duane S.]

Looking good this morning for, as SK put it yesterday, 'a disturbance in the force'!

Strong wave1 activity pretty much nailed on and as was forecast back a week ago.

Uptick in wave2 here as well, hints of trop led as well?

Temps about to skyrocket at 10hpa, unlikely to be without consequence for a vortex looking to get its act together...

Upper strat in a state of disarray again, u winds now a gentle westerly breeze at all levels and a reversal over the pole at the top which will be one to watch

Edited December 22, 2014 by s4lancia

[damianslaw]

Just wondering how the stratosphere is behaving right now compared to this time 2 years ago - I seem to recall forecasted predictions of significant SSW around this time in 2012 and I think one occurred early in Jan changing the northern hemisphere pattern.

 

Its been a rather confusing picture so far - many conflicting signals it appears seem to be cancelling themselves out and predictions coming under pressure.

 

Reading the posts above we appear to be entering the period when expected major warming should be taking place, but downstream affects may not occur until mid Jan at the earliest and quite likely late Jan, whereby back in Nov many predictions were for such effects to rapidly take hold at the turn of the year..

 

Will be keeping an eye on this thread with keen interest over the Christmas-New Year period - its is always very level headed in complete contrast to the Model Discussion thread which unfortunately not doubt will become a playground over the next week or so. Too much volatility in the models and wide margins for error making looking beyond about 120 hours quite pointless at the moment.

[ITSY]

 

Not a chart you see everyday...

[lorenzo]

Image courtesy of weatherbell, sorry only kidding., thank you WSI.

 

Strat is getting torched.

 

 

[No Balls Like Snow Balls]

From WSI

ECM showing significant warming in the stratosphere. Not quite a split of the vortex though.

[feb1991blizzard]

Reasonable displacement on the GFS 18z.

 

 

http://www.instantweathermaps.com/GFS-php/showmap-strat.php?run=2014122218&var=HGT&lev=1mb&hour=384

 

 

However, this is the most interesting chart from the parallel, would like to see the height charts for this.

 

 

 

 

[Paul_1978]

Reasonable displacement on the GFS 18z.

 

 

http://www.instantweathermaps.com/GFS-php/showmap-strat.php?run=2014122218&var=HGT&lev=1mb&hour=384

 

 

However, this is the most interesting chart from the parallel, would like to see the height charts for this.

 

 

Interesting stuff, but 300+ hours away???

[feb1991blizzard]

Interesting stuff, but 300+ hours away???

 

The warmings are underway and yes any possible SSW has been delayed at the very least, The problem with these charts is we cant seem to get a string of these runs, I would be much more confident if we could, certainly infinitely more confident than Surface / Troposphere charts verifying at those stupid ranges.

[snowking]

*standard on phone so no charts disclaimer*

Well pretty encouraging output this morning on the Berlin charts. Reversal at 1mb by day 9 in response to the large wave 1 attack, though there is an uptick once again by day 10 as this relents a little. Wave 2 then increases from the top around days 8/9, before we start to see concurrent upwelling and downwelling temperature waves by day 10.

Overall then a pretty inhospitable environment for a polar vortex.

Tropospherically there are a few factors in current NWP leading to the strong vortice shown to set up across Canada, but this is mostly driven I would suspect by the large wave 1 attack stratospherically taking place from the Pacific side, pushing more energy towards our half of the Northern Hemisphere. What I would say though is that this is a particularly fluid situation and it is perhaps best not to take too much tropospheric output beyond day 5-6 as gospel right now until we see what the effect of all this activity above is.

Support currently from the lower stratosphere for this but with the increase in wave 2 shown by day 10 the final effect could be something very different.

You feel that something has to give sooner or later, with nothing particularly resembling a vortex showing for the foreseeable in the stratosphere.

SK

[KyleHenry]

MT event via ECMWF Berlin well underway

http://www.geo.fu-berlin.de/en/met/ag/strat/produkte/winterdiagnostics/index.html

At 96 hours the peak temperature forecast to be 30 Degrees Celsius assassination of PV at 1 hPa level.

U winds on 10 hPa level at 60 degrees showing reversal at - 20m/s

High concentration of Ozone BDC above Bering Sea

http://ozonewatch.gsfc.nasa.gov/monthly/monthly_2014-12_NH.html

Keeping the warming on Atlantic and Eurasian side of NH.

Waiting to see where down welling could occur.

I agree with Snowking Canada to Canadian Arctic Ocean for bulk of PV as it presently stands.

Leaves cold for UK to come from PM shots and until down welling results. Greenland and Scandinavian ridging both still an option with the Scandi having a higher percentage chance.

Edited December 23, 2014 by KyleHenry

[feb1991blizzard]

Here is an example of a decent warming, I don't think even this was a technical SSW though, if I can remember rightly.

 

http://www.meteociel.fr/modeles/gfse_cartes.php?mode=10&ech=6&heure=0&jour=20&mois=1&annee=2012&archive=1&carte=1

 

 

EDIT : Of course it must be said though that we were up against a really rampant PV that year.

Edited December 23, 2014 by feb1991blizzard

[Recretos]

Reasonable displacement on the GFS 18z.

 

 

http://www.instantweathermaps.com/GFS-php/showmap-strat.php?run=2014122218&var=HGT&lev=1mb&hour=384

 

 

However, this is the most interesting chart from the parallel, would like to see the height charts for this.

 

 

 

 

I am completely "timeless" during these holidays, but nonetheless here is the 10mb gph, since I made it because I was wondering too about the height profile.

[feb1991blizzard]

I am completely "timeless" during these holidays, but nonetheless here is the 10mb gph, since I made it because I was wondering too about the height profile.

 

 

Cheers, although decent I thought it might have shown signs of a split although knew it was a long shot.

[No Balls Like Snow Balls]

From WSI

Anomalies greater than 25C at 10mb by New Years Day, but the core of the stratospheric vortex is still intact.

[Recretos]

From WSI

Anomalies greater than 25C at 10mb by New Years Day, but the core of the stratospheric vortex is still intact.

B5jNLIAIUAAnoGr.jpg

 

WSI has good graphics, but they sometimes have a hard time interpreting whats on them. That is by no means an intact vortex. It has a cross polar flow, with the vortex zonal momentum nicely reduced and the core split on two individual units under wave 2 pressure. 

 

Just a side note on NAEFS: Its low res, and its a combination of CMC ENS and GEFS, basically it has a reduced top to 10mb.

[lorenzo]

This is the 12z GFS at the problem level of 30mb, hefty split vortex and as I understand it the ECM follows suit and enhances the signal.

 

Things are about to get very interesting, very quickly..

 

Other height levels from same time stamp