Jump to content
Snow?
Local
Radar
Cold?
IGNORED

Stratosphere Temperature Watch 2013/2014


Recommended Posts

Posted
  • Location: Burton-on-Trent (90m), Larnaka most Augusts
  • Location: Burton-on-Trent (90m), Larnaka most Augusts

Spotted something on twitter today that is related to the following paper that I have been trying to dissect as much as I can;

 

http://journals.ametsoc.org/doi/pdf/10.1175/2007JCLI1725.1

 

This is directly related to the following graphic;

 

https://pbs.twimg.com/media/BdtEJg7CUAI_Qpp.png:large

 

From that paper it states that in relation to Cohens research that a Siberian High combining with an Aluetian Low can precede a SSW by approx a month or so. Clearly that would take us into February and not late January, but still may well tie in with the winter longer thoughts as to why one may well happen. I know there are viewers of this thread who have a better understanding of these broader northern hem patterns than I, of which as I mentioned the other day I was trying to get my head around in direct relation to the stratosphere. But unless I am way off the mark, it would seem that the Siberian High/Aluetian Low setup is about to take place...

 

This seems to tie in with the strong signals for further wave 1 activity and a displaced vortex rather than a split in time with a possible/likely SSW sometime around the opening week or so of February.

 

We shall see...

 

Matt.

 

Here's the image showing the precursors to wave 1 (top pictures) and wave 2 SSWs. As you said the main feature for a wave1-lead SSW is the Siberian High and Aleutian low.

 

Posted Image

  • Like 1
Link to comment
Share on other sites

Posted
  • Location: Carryduff, County Down 420ft ASL
  • Location: Carryduff, County Down 420ft ASL

The latest MERRA data shows that the 9th recorded the 2nd highest (out of 12793 days) combined 10mb wave 1+2 amplitude of geopotential height at 60°N, a little behind 12/02/89 which was followed by an SSW 9 days later.

Now that is a RAMP.A decent spike in the 30hpa temps, lets hope it continues upwards quickly.http://www.cpc.ncep.noaa.gov/products/stratosphere/temperature/30mb9065.gif
  • Like 1
Link to comment
Share on other sites

Posted
  • Location: Waddingham, Lincolnshire. (9m asl)
  • Weather Preferences: Anything newsworthy, so long as it's not in the Daily Express
  • Location: Waddingham, Lincolnshire. (9m asl)

The latest MERRA data shows that the 9th recorded the 2nd highest (out of 12793 days) combined 10mb wave 1+2 amplitude of geopotential height at 60°N, a little behind 12/02/89 which was followed by an SSW 9 days later.

Interitus, is this shown on some form of chart/graph anywhere - would be interesting to see it visually? Also, do you know if SSW's have followed similar combined amplitude incidences (e.g. 1st, 3rd, 4th, 5th highest etc). Sorry if I'm being a dunce, sincere question from thick Northerner!

Edited by supernova
  • Like 1
Link to comment
Share on other sites

Posted
  • Location: Toronto, On
  • Location: Toronto, On

This would tie in with the suggestion of heights to the NE receding away eastwards in response probably to a reenergised polar vortex moving towards Greenland. For medium term prospects i.e. as we move through the second half of January this isn't a good situation for UK snow and cold prospects, however, I'm encouraged by the prospects of wave breaking and strat warming perhaps helping to develop stronger heights to the west of the Greenland and in the vicinity of Canada and I highly doubt the polar vortex can develop the strength it has in recent weeks - February thus could see a scandi trough scenario and a negative west based NAO pattern with a much weaker diffuse Jetstream.

 

Can anyone shed light on why the polar vortex has been so cold and strong so far this winter... a number of people were calling for a very dry December, how wrong? Can't help but think the aluetian heights during November helped to lock and intensify the PV in situ over Canada - and this was all in response to the PDO and ENSO state. Anyone help with an explanation?

In +QBO and Smax years(when jan SSN is above 95) the PV tends to stay stronger then normal for the first half of winter before the HT effect begins to turn that around from mid january onwards. Cohen's SAI also backed up a strong early season vortex as the Oct snow cover had little to no advance which helps keep the north siberian high anomalously weak. It also helps keep Eddy heat flux at or below normal from Oct through Dec. Notice how that is beginning to turn around, with a recent spike in EP heat flux.

 

The north pac low is expected to strengthen over the next 15 days which will only help weaken the already wave 2 ravaged vortex. We may see enough warming/heat flux by D7-9 to displace the vortex completely or this could take until the last few days of Jan into early feb as the bering sea low return's. Either way, we are likely looking at a significant SSW event occurring, which should have major sfc implications starting anywhere between Feb 2nd-20th IMO. Interesting regime change on the way...

Edited by blizzardof96
  • Like 8
Link to comment
Share on other sites

Posted
  • Location: Windermere 120m asl
  • Location: Windermere 120m asl

In +QBO and Smax years(when jan SSN is above 95) the PV tends to stay stronger then normal for the first half of winter before the HT effect begins to turn that around from mid january onwards. Cohen's SAI also backed up a strong early season vortex as the Oct snow cover had little to no advance which helps keep the north siberian high anomalously weak. It also helps keep Eddy heat flux at or below normal from Oct through Dec. Notice how that is beginning to turn around, with a recent spike in EP heat flux.

 

The north pac low is expected to strengthen over the next 15 days which will only help weaken the already wave 2 ravaged vortex. We may see enough warming/heat flux by D7-9 to displace the vortex completely or this could take until the last few days of Jan into early feb as the bering sea low return's. Either way, we are likely looking at a significant SSW event occurring, which should have major sfc implications starting anywhere between Feb 2nd-20th IMO. Interesting regime change on the way...

Thanks for the response. I'm a firm believer that mother natures balances herself out to achieve in the aim of maintaining an equilibrium state - with this in mind, and given we have seen a rampant atlantic at a level preety unprecedented it is only a matter of time before we see a major switch to something opposite we have experienced- February could turn out to be very different indeed - just a hunch and I think will be very different, it feels similar to Nov 2009 after the unprecedented very wet conditions of that month and we know what happened in mid December....

Link to comment
Share on other sites

Posted
  • Location: Toronto, On
  • Location: Toronto, On

Since correlations seem to be a point of interest at the present time, I also decide to have a go at them. Posted Image

 

Awesome work Recretos! Based on some of my research regarding QBO phase correlation's with upper strat temps, ENSO, PDO and solar activity are very important factors to consider when relating the QBO to the strength of the NAM state. This is how I look at it, going from most to least favourable conditions for a major SSW event or intensification of the BDC. Obviously never a linear correlation, as other factors can make major differences in these years(strength of EAMT events, RWT setup's, East Pac ridging, and ozone from previous ENSO events).

1. -QBO, Smin, any ENSO/PDO conditions(see a major SSW event almost 100% of the time in the DJF period)

2. -QBO, Smax, la nina or neutral ENSO

3. -QBO, Smax, el nino/+PDO

4. +QBO, Smax, +PDO, el nino

5. +QBO, Smax, -PDO, la nina/neutral ENSO

6. +QBO, Smin, +PDO

7. +QBO, Smin, -PDO/la nina

Edited by blizzardof96
  • Like 5
Link to comment
Share on other sites

Posted
  • Location: Liverpool - 23m ASL
  • Weather Preferences: Cold, snowy winters and hot, sunny summers!
  • Location: Liverpool - 23m ASL

You know you're desperate for some crumb of cold comfort when you're a university student, agonising over the strato thread at 1am on a Saturday night... Posted Image

 

Thanks again for your hard work in here guys! 

  • Like 4
Link to comment
Share on other sites

Posted
  • Location: Ås, Norway
  • Location: Ås, Norway

The important thing to note, is the fact that even tho these correlations tells us a possible relationship between different parameters, they dont tell us what exactly is the relationship, or more importantly, who is the dominant one. For example, if I correlate the QBO and 30mb zonal wind, I know that the wind is the dominant over the index, since the index is calculated from that exact parameter. 

Or for example NAO index and surface temperature, where NAO index is "dominant" since it is calculated from the pressure differences or the "pattern" which determines the surface temperature. The correlation with the sfc. temperature is weaker (tho still very high), since the surface temperature is much more sensitive to the pattern differences, while the area that "calculates" NAO has much more tolerance to these differences. This is the same way I made correlations last year, when I was searching for SSW precursor patterns simply by "cross-linking" different indexes/parameters.

 

 

So all in all, these correlations are a great tool, but some basic knowledge in meteorology is required, so you can correctly interpret the results. 

 

 

 

Thank you so much for your great work, Recretos :) Interesting to see a strong correlation between NAO and 30hpa gph. I wanted to do this myself, but did not know how Posted Image Such nice graphics! Between you and me, ~0.6 is regarded as pretty decent in ecology (for field data). 

 

And you are completely right, an important thing regarding correlations is that they do not (always) provide insight in causalities. I'am pretty sure I can strongly correlate (with correlation coefficient of >0.7) the number of posts in this thread with the time till onset date of a major warming. This does not mean that increasing the amount of posts in this thread increases our chances of an SSW, of course. A correlation coefficient is more valuable if the causalities are known, i.e.: there is supporting theory. 

 

By the way, those GEFS means, they look ok, don't they?

  • Like 1
Link to comment
Share on other sites

Posted
  • Location: Irlam
  • Location: Irlam

Thanks for the response. I'm a firm believer that mother natures balances herself out to achieve in the aim of maintaining an equilibrium state - with this in mind, and given we have seen a rampant atlantic at a level preety unprecedented it is only a matter of time before we see a major switch to something opposite we have experienced- February could turn out to be very different indeed - just a hunch and I think will be very different, it feels similar to Nov 2009 after the unprecedented very wet conditions of that month and we know what happened in mid December....

Winter 2009-10 wasn't actually dry overall, it was actually wetter than winters 2008-09, 2010-11 and 2011-12 for England and Wales not one of the months were that dry despite the blocking.
  • Like 1
Link to comment
Share on other sites

Posted
  • Location: Nuneaton,Warks. 128m asl
  • Weather Preferences: Snow then clear and frosty.
  • Location: Nuneaton,Warks. 128m asl

Yes those are encouraging signs of zonal winds decreasing further down within the the 10 day range Tony.

Temperature forecasts now trending towards average at last after such a cold Stratosphere profile this Winter.

GFS recent runs showing further stress on the vortex at both middle and lower levels in the 10-15day range.

post-2026-0-61983400-1389530808_thumb.pnpost-2026-0-13358600-1389530816_thumb.pn

 

those from the 06z run following the trend from previous outputs.

 

Not yet within range of the 500hPa modeling but we have seen some weakening of the Atlantic flow already from recent wave activity so lets hope continued wave activity forecasted will further undermine the vortex until it finally relents.

 

  • Like 6
Link to comment
Share on other sites

Posted
  • Location: Weardale 300m asl
  • Weather Preferences: Snow
  • Location: Weardale 300m asl

Some plots from this mornings Berlin data..

 

Wave 1 strong from day 7 and sustained, usually GPH increases as this ticks toward verification.

Posted Imageecmwfzm_ha1_f168.gif

 

Out at day 10 the zonal wind profile looking very weak. Speaking of correlation, would be nice to see the heat flux plot below correlated with the position of the jet. i.e how much the downwelling flux shreds the jetstream/displaces southward

Posted Imageecmwfzm_u_f240.gifPosted Imageecmwfzm_vt_f240.gif

Posted Imagetime_pres_WAVE1_MEAN_JFM_NH_2014.gifPosted Imagetime_pres_WAVE2_MEAN_JFM_NH_2014.gif

 

Some poleward EP flux beginning to appear.

Posted Imagefluxes.gif

 

Also, from GWO EAMT underway, although unsure how much this will do as we start from GLAAM bottomed out at -3SD, first plot shows where atmosphere was a few days ago when the easterly receded GWO orbit solid into phase 2, second plot where things are now and appears to be cycling again.

Posted Imagegltaum.90day.gifPosted Imagegfsgwo_3.pngPosted Imagegfsgwo_1.png

 

All encouraging signs that the vortex is slowly suffering from the mighty attempts to bring it down, am sure other winter vortex would have been toast by now. Am wondering if it can hang on and survive January. That Wave 1 attack will make it susceptible to further hits. I'll leave it to Recretos to figure out where the cold is going to land. ( convinced he is a reincarnation of Einstein).

 

 

I've been sent here by the Models thread to lighten my mood of despair  - never mind the PV surviving January - I'm wondering whether I can survive another couple of weeks of this nightmare tundra of mud, soaking wet grass and that really irritating feeling of being cold without a jumper, then once you're put one on, feeling too hot…  Posted Image

  • Like 3
Link to comment
Share on other sites

Posted
  • Location: Lincolnshire - 15m asl
  • Weather Preferences: Frost and snow. A quiet autumn day is also good.
  • Location: Lincolnshire - 15m asl

In +QBO and Smax years(when jan SSN is above 95) the PV tends to stay stronger then normal for the first half of winter before the HT effect begins to turn that around from mid january onwards. Cohen's SAI also backed up a strong early season vortex as the Oct snow cover had little to no advance which helps keep the north siberian high anomalously weak. It also helps keep Eddy heat flux at or below normal from Oct through Dec. Notice how that is beginning to turn around, with a recent spike in EP heat flux.

 

The north pac low is expected to strengthen over the next 15 days which will only help weaken the already wave 2 ravaged vortex. We may see enough warming/heat flux by D7-9 to displace the vortex completely or this could take until the last few days of Jan into early feb as the bering sea low return's. Either way, we are likely looking at a significant SSW event occurring, which should have major sfc implications starting anywhere between Feb 2nd-20th IMO. Interesting regime change on the way...

 

Great post - thank you.

  • Like 2
Link to comment
Share on other sites

Posted
  • Location: Essex, Southend-On-Sea
  • Weather Preferences: Warm, bright summers and Cold, snowy winters
  • Location: Essex, Southend-On-Sea

Mega ramp from latest GFS.

 

Posted Image

 

Immediate signs are seen on the trop.

 

Posted Image

  • Like 1
Link to comment
Share on other sites

Posted
  • Location: Brighton (currently)
  • Location: Brighton (currently)

Mega ramp from latest GFS.

 

Posted Image

 

Immediate signs are seen on the trop.

 

Posted Image

What is the immediate sign on the troposphere?

 

Karyo

Link to comment
Share on other sites

Posted
  • Location: st albans
  • Location: st albans

whilst there does indeed seem to be a 'quick downwelling ssw' trop response at the end of the gfs op run, (the evolution of the post T300 part of the run carries all the hallmarks of a quick trop response to a ssw), i cant accept there is a connection.  what is shown on that gfs strat chart is at 10hpa - i cannot conceive that the trop will move in tandem with it.  has to be co incidence.  we would expect to see that trop response within a week of an actual ssw (if it propogated quickly). there is no ssw shown on the 12z op - just another asian warming.

  • Like 1
Link to comment
Share on other sites

Posted
  • Location: Manchester Deansgate.
  • Weather Preferences: Heavy disruptive snowfall.
  • Location: Manchester Deansgate.

whilst there does indeed seem to be a 'quick downwelling ssw' trop response at the end of the gfs op run, (the evolution of the post T300 part of the run carries all the hallmarks of a quick trop response to a ssw), i cant accept there is a connection.  what is shown on that gfs strat chart is at 10hpa - i cannot conceive that the trop will move in tandem with it.  has to be co incidence.  we would expect to see that trop response within a week of an actual ssw (if it propogated quickly). there is no ssw shown on the 12z op - just another asian warming.

 

 

Yes - not even close to an ssw, one may well follow if that run carried on but not even close to a zonal wind reversal yet, trop response can take as long as 10-15 days!!!

 

http://www.instantweathermaps.com/GFS-php/showmap-strat.php?run=2014011212&var=HGT&lev=10mb&hour=384

Edited by feb1991blizzard
Link to comment
Share on other sites

Posted
  • Location: hertfordshire
  • Location: hertfordshire

I wonder with the wave 2 fading and the stronger wave on the Siberian side being able to

spin the vortices anti- clockwise crosspolar on to a meridian axis if you like would this have

been better for our chances of cold.

Where as now it is starting to look as if a second very strong (perhaps SSW) warming is likely to

halt this process and push the vortex (more circular in shape) back towards canada and

Greeland. I suppose you could argue that it might improve our chances of more easterly type

weather during february perhaps and any strong warming poleward has to be better than what

we have, but I did like the look of the crosspolar set up and how this may have manifested itself

down into the troposphere.

Link to comment
Share on other sites

Posted
  • Location: hertfordshire
  • Location: hertfordshire

whilst there does indeed seem to be a 'quick downwelling ssw' trop response at the end of the gfs op run, (the evolution of the post T300 part of the run carries all the hallmarks of a quick trop response to a ssw), i cant accept there is a connection.  what is shown on that gfs strat chart is at 10hpa - i cannot conceive that the trop will move in tandem with it.  has to be co incidence.  we would expect to see that trop response within a week of an actual ssw (if it propogated quickly). there is no ssw shown on the 12z op - just another asian warming.

Is it not true that tropospheric heights are a precursor to SSW warmings and it is this

that the model is showing rather than the effects of the warming.

Link to comment
Share on other sites

Posted
  • Location: st albans
  • Location: st albans

Is it not true that tropospheric heights are a precursor to SSW warmings and it is thisthat the model is showing rather than the effects of the warming.

that can be the case cc. I was just pointing out that the 12z fi op was a classic post ssw type run but in no way a response to the events shown at 10 hpa late in the run. Similarly, the upper strat would not respond in tandem to the trop pattern but take a little time. (Likely less than downwelling though ). Ed?
Link to comment
Share on other sites

Guest
This topic is now closed to further replies.
×
×
  • Create New...