Stratosphere Temperature Watch 2015/2016

[Ravelin]

17 hours ago, Vorticity0123 said:

As can be seen here, in a region ecompassing the east of the UK and the northern parts of the Netherlands, temperatures are below -80*C, which might result in polar stratospheric clouds becoming visible just after sunset (so a few hours ago by now).

As predicted, photos of 'strange clouds' from this morning in NE Scotland...

 

 

[feb1991blizzard]

OH YES BABY!!!!!    Split SSW inbound.

 

And not just any split either, a wave 2 split slicing straight through Greenland if it went any further out.

Edited January 29, 2016 by feb1991blizzard

[Ruben Amsterdam]

Split yes, but SSW...?

[feb1991blizzard]

3 minutes ago, Ruben Amsterdam said:

Split yes, but SSW...?

Wouldn't be long coming afterwards me thinks, in any case as long as that split maintained for any length of time as seen there, that would be enough to do the job, all conjecture yet anyway.

The warming still going strong right up top on this run at the end which on a few previous runs it had shown signs of waning.

Edited January 29, 2016 by feb1991blizzard

[karyo]

36 minutes ago, feb1991blizzard said:

Wouldn't be long coming afterwards me thinks, in any case as long as that split maintained for any length of time as seen there, that would be enough to do the job, all conjecture yet anyway.

The warming still going strong right up top on this run at the end which on a few previous runs it had shown signs of waning.

Yes, this is quite a change in the 6z and we need to see this theme maintained in the following runs.

As we all know by now, the 6z gfs tends to be quite enthusiastic with the degree of warming.

[feb1991blizzard]

5 minutes ago, karyo said:

Yes, this is quite a change in the 6z and we need to see this theme maintained in the following runs.

As we all know by now, the 6z gfs tends to be quite enthusiastic with the degree of warming.

Not always this winter, sometimes it has been the other way around, what has been a theme though is that any really stellar run has always at least slightly downgraded on the next run so I would expect some kind of downgrade, I really wouldn't know exactly what to expect on the 12z because this was totally out of the blue, if it is maintained over the 12 and 18z though then I would be interested, if you were to push me though, I would say the 12 will have the larger lobe still over Greenland with much less of a split and the 1mb temperature chart to downgrade somewhat based on about 5 years of experience of watching these charts - hope not though.

[karyo]

1 minute ago, feb1991blizzard said:

Not always this winter, sometimes it has been the other way around, what has been a theme though is that any really stellar run has always at least slightly downgraded on the next run so I would expect some kind of downgrade, I really wouldn't know exactly what to expect on the 12z because this was totally out of the blue, if it is maintained over the 12 and 18z though then I would be interested, if you were to push me though, I would say the 12 will have the larger lobe still over Greenland with much less of a split and the 1mb temperature chart to downgrade somewhat based on about 5 years of experience of watching these charts - hope not though.

The truth is that the 0z tried for a split but failed and reverted to the vortex regaining control over Greenland but with lesser strength.

Let's hope it is a new trend.

[Nouska]

You always know things are getting a bit more interesting when the JMA issue their first 'strat alert' of the winter.

http://ds.data.jma.go.jp/tcc/tcc/products/clisys/STRAT/text/20160127.txt

[Allseasons-Si]

A bit strat related,gav's latest video from yesterday

 

 

[Weather-history]

What do the pundits make of this?

https://mobile.twitter.com/DTVaWeatherman/status/693056949345193984/photos

 

[Dennis]

[winterof79]

33 minutes ago, Weather-history said:

What do the pundits make of this?

https://mobile.twitter.com/DTVaWeatherman/status/693056949345193984/photos

 

Coupled with this from fergie

"Indeed so. As I mentioned yesterday, we must expect a raft of model outcomes as suites get to grips (or mostly not, currently) with broadscale pattern change and drivers next month. Many should recall the similar wild fluxes we saw ahead of last key pattern change earlier this month (to the colder blocking) albeit for different reasons. The prognosis for Feb was discussed last week at Exeter (seasonal outlook meeting, held monthly) and since then, there's been no strong reason to shift from the views I outlined yesterday re anticipated changes especially from mid-month (when SSW influence likely to be coming into play). 

 

There is something brewing/boiling as those dates are mid month. How fast it propagates or the down dwelling is is out of our hands.I am punting for a quick tropospheric response.I know some think just a displacement but I hope its the big one.

Edited January 29, 2016 by winterof79

[David Morse]

From some of the comments above I'm not sure what people were expecting an SSW event would look like :-)

Really, what we have in the GFS forecast is as clear a SSW event that you could get in my view. The GFS is showing a peak temp of -15C on the 6th Feb, an increase of 30C in a matter of 36 hours. Furthermore at 384 hours out it sunders the Strat PV in two on the 06z GFS run.

Isn't this what everyone's been looking for all winter long? :-)

 

 

[John Badrick]

53 minutes ago, David Morse said:

From some of the comments above I'm not sure what people were expecting an SSW event would look like :-)

Really, what we have in the GFS forecast is as clear a SSW event that you could get in my view. The GFS is showing a peak temp of -15C on the 6th Feb, an increase of 30C in a matter of 36 hours. Furthermore at 384 hours out it sunders the Strat PV in two on the 06z GFS run.

Isn't this what everyone's been looking for all winter long? :-)

 

 

Chiono, do you concur??

[phil nw.]

56 minutes ago, David Morse said:

From some of the comments above I'm not sure what people were expecting an SSW event would look like :-)

Really, what we have in the GFS forecast is as clear a SSW event that you could get in my view. The GFS is showing a peak temp of -15C on the 6th Feb, an increase of 30C in a matter of 36 hours. Furthermore at 384 hours out it sunders the Strat PV in two on the 06z GFS run.

Isn't this what everyone's been looking for all winter long? :-)

 

 

We have seen quite a lot of w1 warmings at the top for some time and indeed a displacement is now underway but as i understand things we are not yet seeing a technical SSW as there is still no reversal of zonal winds forecasted at 60n at the 10hPa level.

http://users.met.fu-berlin.de/~Aktuell/strat-www/wdiag/eczm.php?alert=1&forecast=all&var=u&lng=eng

the mid-level core still remains cold out to 7/2(day 10) on the ECM charts

http://users.met.fu-berlin.de/~Aktuell/strat-www/wdiag/eczm.php?alert=1&forecast=all&var=t&lng=eng

The 06z 30hPa pressure chart at 384hrs.

 

Certainly the vortex is being pushed around and stretched but not yet being shredded.

[chionomaniac]

1 hour ago, John Badrick said:

Chiono, do you concur??

Here is the NW GFS 10hPa chart at day 16.

 

Technically, this is not a SSW (reversal at 60N and 10hPA) but may lead to one - though caveats that this is again day 16 and the warming is reducing by day 14 so the split may not be strong enough. 

A good sign (though we have seen many of them) and backed up by the EPS which show a wave 1 displacement followed by wave 2 split.

 

So, in short we are seeing another GFS FI chart that could lead to a SSW, but no SSW showing yet. 

[feb1991blizzard]

Still there on the 12z and if anything its ever so slightly strengthening again right at the end

.

[feb1991blizzard]

The fact that the warming is still there right at the end, at the top, does this mean that there is a mountain torque event still having impacts at the end of the run?

I'm not sure ive ever seen such replication all the way down the strat, the split is mirrored almost all the way from 1mb down into the troposphere.

Edited January 29, 2016 by feb1991blizzard

[Singularity]

It looks pretty funky at the 30 hPa level on the 12z (see in MOD thread), signs of wave-2 impacts but tenuous in the Atlantic. A good trend to continue with... here's hoping!

[chionomaniac]

56 minutes ago, feb1991blizzard said:

The fact that the warming is still there right at the end, at the top, does this mean that there is a mountain torque event still having impacts at the end of the run?

I'm not sure ive ever seen such replication all the way down the strat, the split is mirrored almost all the way from 1mb down into the troposphere.

Jan 2009 - the ideal split SSW - was the same. And that had instant trop results from the easterly.  The GFS can overestimate the MT events though as well.

[feb1991blizzard]

1 hour ago, chionomaniac said:

Jan 2009 - the ideal split SSW - was the same. And that had instant trop results from the easterly.  The GFS can overestimate the MT events though as well.

Cheers, that was before my time, I never had any idea about the effect of the Strat then, in fact it was only that event (missing out by 5 miles on a big snow event) that rekindled my enthusiasm, I had practically given up by then of ever seeing blocking occurring again, back in the day in the 80s all we had was surface charts on countryfile, I have briefly sifted through some of the strat threads since though and that 09 event did look the best of the lot, it was like a knife through butter, wave 2 split events look more controlled to me and to have longer lasting implications.

[David Morse]

5 hours ago, phil nw. said:

We have seen quite a lot of w1 warmings at the top for some time and indeed a displacement is now underway but as i understand things we are not yet seeing a technical SSW as there is still no reversal of zonal winds forecasted at 60n at the 10hPa level.

Yes there has been some persistence of W1 warmings; but I have not seen ALL winter long the temp go higher than -30? Anyhow isn't what you're saying a little chicken or egg? The "technical" aspect of a wind reversal only occurs after the warming event, not before it, you need to see this level of incursion before the reversal of the winds surely?

 

[David Morse]

GFS 12z 384hrs clearly shows the start of a wave 2 event IMHO.

[phil nw.]

38 minutes ago, David Morse said:

Yes there has been some persistence of W1 warmings; but I have not seen ALL winter long the temp go higher than -30? Anyhow isn't what you're saying a little chicken or egg? The "technical" aspect of a wind reversal only occurs after the warming event, not before it, you need to see this level of incursion before the reversal of the winds surely?

 

Not quite sure what point you are making David.

Current forecasts do show continued warmings but not to the extent of  a SSW, which is simply all i was saying.

It may or may not lead to something better but we simply don't know from current outputs.

[chionomaniac]

59 minutes ago, David Morse said:

GFS 12z 384hrs clearly shows the start of a wave 2 event IMHO.

The wave 2 event is pretty well established at this point