Stratosphere Temperature Watch 2011/2012

[LomondSnowstorm]

As far as I am concerned there is no major change in the suggested outlook.

Back to Scandi heights eventually transferring to the NW.

Thank you, typical FI model volatility rather than any fundamental change looks most probable then.

[chionomaniac]

What's interesting (worrying?) C, is that the models seem to be reforming the vortex over the last couple of days despite what the strat seems to say... What's happening?

In these cases it's always best to wait a couple of days and then see what the trend is.

[syed2878]

Hi chio a question. if there's no change in the strat and a greenland blocking is likely to happen how come then the met arnt picking up on that? Surely for the met to change their 30day outlook they must be picking up some signoel. Or have i got that wrong. Tthanks

[chionomaniac]

Hi chio a question. if there's no change in the strat and a greenland blocking is likely to happen how come then the met arnt picking up on that? Surely for the met to change their 30day outlook they must be picking up some signoel. Or have i got that wrong. Tthanks

I don't know and can't answer that. Perhaps because the vortex reforms before WAA has had sufficient time to develop. The only other suggestion that I have is to ask them.

[syed2878]

Thanks for the reply chio. Keep up the good work.

[leicsnow]

The 06z GFS has only a brief strengthening of the PV. Does this tie in with any stratospheric warming events which could cause the PV to shatter after tightening up initially?

Edited February 6, 2012 by Tellow

[Paul]

For those wanting to learn a little more about the stratosphere we now have a tutorial online which you can read here (thanks to Ed for writing it)

http://www.netweather.tv/index.cgi?action=stratosphere-tutorial;sess=

You can also view the latest strat charts from the GFS on their own page now:

http://www.netweather.tv/index.cgi?action=stratosphere;sess=

[Paul White.]

For those wanting to learn a little more about the stratosphere we now have a tutorial online which you can read here (thanks to Ed for writing it)

http://www.netweathe...-tutorial;sess=

You can also view the latest strat charts from the GFS on their own page now:

http://www.netweathe...atosphere;sess=

Well done Ed and NetWeather that was very informative and not too technical for my slow brain.

Paul

[TobyT]

Chio I was wondering if there are any major changes to the strat forecast since the last update.

Looks like the models are are beginning to flirt with the idea of a GH but that seems to be about as far as they go with it,they then seem to be going with a stronger jet and a more mobile Atlantic theme around T+120 or so, having said that the models are all over the shop and have been for a while now.Would be interested to get your take on things as always as I am just a novice, thanks for all your hard work I really do enjoy reading your informed posts.

Update, the latest model runs looking more favourable to a blocking pattern for a GH if I am reading things right.

Edited February 8, 2012 by TobyT

[UV-RAY]

Well after enduring one of the least snowiest winters on record for these parts, I can only say that without any stratospheric warming early in the season, we have endured a truly awful winter for many parts of NW England, Scotland, and Ireland. A truly forgettable winter for many away from the South and East.

[kold weather]

Seven of Nine, I think thats sheer bad luck in many ways, for example had that Russian High set-up say 150 miles further west you weather would have been very different and probably more akin to what the SE has had.

[karyo]

The mean zonal winds are rocketing again at the 1hpa level: http://wekuw.met.fu-berlin.de/~Aktuell/strat-www/wdiag/ts.php

Is this what is ruining our chances for more favourable blocking?

The stratospheric temperatures at the 10hpa level are cooling rapidly but the crucial 30hpa is still above average.

Karyo

[UV-RAY]

Seven of Nine, I think thats sheer bad luck in many ways, for example had that Russian High set-up say 150 miles further west you weather would have been very different and probably more akin to what the SE has had.

But if it had set up 150 miles further East, then all parts would have missed out. All good Synoptics rely on luck for the UK, but a strong PV and an Azores high have more or less killed winter off for NW Britain. Easterlies are bobbins in the majority of cases for NW UK.

[Continental Climate]

I just want to say that this has been a fantastic thread that I have read daily especially through the dark days of Dec and Jan and I imagine it has kept a lot of people's spirits up as well.

I do expect this thread to become a lot quieter now as we head into mid feb. As i mentioned in another thread all it would have took is for the siberian high to be 300-400 miles further west and bingo. In terms of the NH as a whole that is a tiny distance, but alas it was not meant to be and the really deep cold stayed just over the channel.

Oh well better luck next year

[Suburban Streamer]

I just want to say that this has been a fantastic thread that I have read daily especially through the dark days of Dec and Jan and I imagine it has kept a lot of people's spirits up as well.

I do expect this thread to become a lot quieter now as we head into mid feb. As i mentioned in another thread all it would have took is for the siberian high to be 300-400 miles further west and bingo. In terms of the NH as a whole that is a tiny distance, but alas it was not meant to be and the really deep cold stayed just over the channel.

Oh well better luck next year

i've had a total 20cms of snow from two snow events in the space of a week! for me thats a miracle lol!

i better say something about the strat before chiono deletes this

zonal winds still looking good at day 6?

and totally agree this has been a brilliant thread!

Edited February 10, 2012 by Suburban Streamer

[chionomaniac]

A quick update today due to time constraints.

At the time of the last update it was suggested that we should be looking at heights rising towards the NW. This was due to a split vortex segment over Greenland which would allow a window of opportunity for tropospheric WAA to build and allow a block to become stained here. This does not look like occurring now and the door opening to the split vortex is closing before this is able to occur with reformation of the polar vortex over Greenland occurring . The trend is to slide this lobe towards the Svalbard end, which would open the door for a NW attack, which could lead to something more pronounced later.

I cannot see the Siberian high breaking back through with the vortex positioning here - and would suggest if we are to get any cold attack it will be from the northwest until things change.

Looking further ahead for the rest of winter it should be noted that mean zonal mean winds at the middle to lower levels of the stratosphere are still reduced and do not look like increasing until we are into March.

This would indicate to me that the tropospheric vortex will still be amenable to blocking during this time; the big question remains of whether it will be in a position to affect us.

Looking back so far this winter, the stratospheric vortex has behaved pretty much as forecast, with the strong early winter vortex giving way after the January wave breaking warming. I know that not all areas have experienced the cold conditions of the SE, but as a means of forecasting any blocking likelihood in the NH pattern, the stratosphere monitoring has proved an invaluable source in helping to predict beyond the reliable timeframe.

[greybing]

But if it had set up 150 miles further East, then all parts would have missed out. All good Synoptics rely on luck for the UK, but a strong PV and an Azores high have more or less killed winter off for NW Britain. Easterlies are bobbins in the majority of cases for NW UK.

'bobbins' ,not heard that word for a while.it should be used more .I have to agree ,it has not been great in the north west ,not bad though [certainly where i am] Edited February 10, 2012 by greybing

[lorenzo]

C, you mentioned a couple of posts ago that you had some ideas for winter 2012-13 in terms of temp profiles and Ozone.. I know for many this is extreme FI but would be interested to hear some early thoughts.

I hope when this thread is archived it is not deleted as many of the evolutions and papers are an invaluable resource, hopefully it can be pinned to next years..

[leicsnow]

C, you mentioned a couple of posts ago that you had some ideas for winter 2012-13 in terms of temp profiles and Ozone.. I know for many this is extreme FI but would be interested to hear some early thoughts.

I hope when this thread is archived it is not deleted as many of the evolutions and papers are an invaluable resource, hopefully it can be pinned to next years..

I too feel it wouldn't hurt to speculate an idea of a starting point for next winter. While it is deep FI there is a difference between seeing a forecast from James Madden forecasting the next winter based on sunspots alone than seeing a good starting point forecast based on stratospheric conditions!

[chionomaniac]

C, you mentioned a couple of posts ago that you had some ideas for winter 2012-13 in terms of temp profiles and Ozone.. I know for many this is extreme FI but would be interested to hear some early thoughts.

I hope when this thread is archived it is not deleted as many of the evolutions and papers are an invaluable resource, hopefully it can be pinned to next years..

The reason I mentioned this is that the low ozone conditions that were experienced at the end of winter 2011 seemed to follow on at the start of this winter. Let's hope the opposite can occur.

[Midlands Ice Age]

C, you mentioned a couple of posts ago that you had some ideas for winter 2012-13 in terms of temp profiles and Ozone.. I know for many this is extreme FI but would be interested to hear some early thoughts.

I hope when this thread is archived it is not deleted as many of the evolutions and papers are an invaluable resource, hopefully it can be pinned to next years..

Lorenzo, Chiro, et al (mods)

Is it not possible to have a new thread for this information?

It would be a valuable research aid for future years if it prooves to verify.

Mid;ands Ice Age

[shedhead]

No posts for 48hrs, is nothing going on in the strat anymore?

[chionomaniac]

No posts for 48hrs, is nothing going on in the strat anymore?

Perhaps I have a life away from net weather as well! I haven't had the time to look at a computer for over 48 hours Shed.

[shedhead]

Perhaps I have a life away from net weather as well! I haven't had the time to look at a computer for over 48 hours Shed.

The question was not specifically posed at you C. Others have posted in the past, admittedly perhaps not with your depth of knowledge/understanding of the subject, but an update from anyone who feels able to contribute would be appreciated.

[chionomaniac]

The overall picture suggests a continuance of the weak vortex conditions at least until the end of the month. I am of the opinion that the increase in mean zonal winds at the 1hPa level is unlikely to affect the troposphere until much later in spring. The remnants of the westerly QBO have now been extinguished from the tropical stratosphere which will assist in keeping the polar stratospheric mean zonal mean winds reduced for the rest of winter. This in effect means that tropospheric considerations will have an enhanced affect during the rest of winter and into early spring.

Edit: just to clarify what I mean by that. Early this winter the tropospheric wave pattern and flow was dominated by the strong stratospheric vortex - this prohibited any chance of HLB's from occurring and prevented local wave breaking events into the centre of the stratospheric polar vortex. We are now in a position where that stratospheric dominance has been removed and tropospheric wave patterns can influence the polar patterns without being immediately squashed by a strong polar vortex.

The turnaround in mid January is impressive.

Edited February 13, 2012 by chionomaniac