Stratosphere temperature watch - 2016/17

[feb1991blizzard]

Cast iron now IMO that this warming wont finish the job, however, got a feeling that the next one wont be far behind, its just the question of whether the full effects will be felt late feb / early March or even later on, by which time most on here wont have the appetite remaining.

[Cheshire Freeze]

1 hour ago, feb1991blizzard said:

Cast iron now IMO that this warming wont finish the job, however, got a feeling that the next one wont be far behind, its just the question of whether the full effects will be felt late feb / early March or even later on, by which time most on here wont have the appetite remaining.

CFS has been steadfast about a blocked March over the past month or so, just like it was in 2013. I assumed this was due to a SSW as soon as I saw the trend emerge

Seems to be very consistent with the location of the potential blocking too. 

About as Greenland based as you can reasonably hope for.

[bluearmy]

Ec 12z from yesterday just reached technical SSW at day 10 but note the zonal winds at day 9 where the stronger flow higher up has been broken apart but nevertheless flushed down to the lower levels. 20m/s at 60N 300hpa isn't going to look too pretty in the trop. It will dissipate but is a normal pre reversal event where the trop gets push from above. We would hope that a downwelling wave is as quick if reversal does occur but checking the zonal winds, the strong reversal at the top of the strat has become pretty gentle by the time it gets to 10hpa and I doubt it will force any reversal much further down that that. 

Incidentally, the strat vortex at 1hpa displaced as far as nw Scotland by day10 with the mid to lower centre residing around Svalbard. 

 

Edited January 23, 2017 by bluearmy

[Summer Sun]

 

[chris55]

Huge changes in the Strat at 1hpa with the PV displaced to Scotland!! And a huge area of high pressure over the pole. But as nick says the forcing as you head down through the atmosphere are a lot less impressive with the displacement only just scraping a technical SSW and not in the most favourable position at this stage.

regardless of the 10hpa charts I find it really impressive what an injection of warm air into the strat can do to the pattern up there!!! 

1hpa today

day 10

 

[bluearmy]

The gefs (and indeed ops) are now consistent on keeping the displaced vortex in the ne scandi/ nw Siberia locale out to day 16

 

[Paul_1978]

44 minutes ago, bluearmy said:

The gefs (and indeed ops) are now consistent on keeping the displaced vortex in the ne scandi/ nw Siberia locale out to day 16

 

Is that good or not so good?

[northwestsnow]

52 minutes ago, Paul_1978 said:

Is that good or not so good?

Its good news paul..

[mb018538]

Interesting that after a big uptick towards the end of January, there are a number of members dropping the AO through the floor. I should add for balance that plenty keep it positive too....but they are clearly wrong, and the trend to cold is definitely right!

[Ali1977]

3 minutes ago, mb018538 said:

Interesting that after a big uptick towards the end of January, there are a number of members dropping the AO through the floor. I should add for balance that plenty keep it positive too....but they are clearly wrong, and the trend to cold is definitely right!

A few started to head negative yesterday, and more today so we are trending in the right direction.  Lets hope the 12z is another upgrade on the block moving further North and heading that little further towards Scandy.  And lets see if we have more GEFS showing the battleground type set up come the end of the month.

[mountain shadow]

1 hour ago, Paul_1978 said:

Is that good or not so good?

Good, but only if the tropospheric PV responds in the same way and we don't retain a lobe over Greenland.

[chris55]

1 hour ago, mountain shadow said:

Good, but only if the tropospheric PV responds in the same way and we don't retain a lobe over Greenland.

 

Edited January 23, 2017 by chris55

[bluearmy]

Fwiw, ec op 12z looks less like a reversal at 10hpa than yesterday 

[booferking]

1 minute ago, bluearmy said:

Fwiw, ec op 12z looks less like a reversal at 10hpa than yesterday 

Roll on spring then.

[Nick F]

Always had a suspicion that this first wave 1 warming into the strat wouldn't do the job in late January. Still chance that another round of wave 1 warming plus more favourable MJO propagation in Feb could have another go at weakening the PV. But it maybe too late to save winter from the Atlantic or Atlantic/Euro block stalemate.

[bluearmy]

19 minutes ago, booferking said:

Roll on spring then.

We are talking semantics here 

a few m/s at 10 hpa doesn't flick a switch

whether the reversal is at 7 or 15 hpa at its lowest isn't important 

whether it's at 50, 60 or 70 degrees north is also not so relevant

its how strong the reversal is at its lowest point and whether it's sustained and looks to work further down towards the trop

At this point, it seems that it's enough to hold the vortex displaced towards scandi/Siberia but not to downwell a reversal wave quickly 

there are signs of a second wave and that may be more effective at forcing some quickish westward movement further down 

[snow mad]

1 hour ago, booferking said:

Roll on spring then.

That's the problem, there probably won't be a spring just like last year! Winter is over this is all to late

[Paul_1978]

1 hour ago, snow mad said:

That's the problem, there probably won't be a spring just like last year! Winter is over this is all to late

There's a good 5 weeks left yet?

[snow mad]

16 minutes ago, Paul_1978 said:

There's a good 5 weeks left yet?

I don't want to pollute this thread with of topic posts but just to say we've had nine weeks already and I bet this winter just fizzles out. I'm now looking forward to the warm sunshine of summer be it in this country or another. 

[Nick F]

As the days get longer the westerly QBO gets stronger, just hope the QBO turns easterly for winter 2017/18 (well overdue anyway) - as the strong QBO state now surely is working against the wave driving/warming that's trying to weaken the PV and zonal winds.

 

Edited January 23, 2017 by Nick F

[Don]

5 minutes ago, Nick F said:

As the days get longer the westerly QBO gets stronger, just hope the QBO turns easterly for winter 2017/18 (well overdue anyway) - as the strong QBO state now surely is working against the wave driving/warming that's trying to weaken it.

 

Just gets better and better......

[bluearmy]

Yesterday's ec op left the zonal flow very slack with little evidence of 'flushing down'. 

looks like the trop will do what the trop wants to do and hopefully the strat will give it a bit of help in dropping the AO neg 

[Ladyofthestorm]

11 hours ago, Don said:

Just gets better and better......

Are you being sarcastic or is this good news for cold weather fans?

[Nick F]

3 minutes ago, Ladyofthestorm said:

Are you being sarcastic or is this good news for cold weather fans?

Not great to get a weaker polar vortex and greater chance of high latitude blocking which would greatly increase chances of deep cold and snowy spell.

[Nouska]

We go from this ...

to this ....                

The models will be playing around with what the effects are at the surface but the current move to a southerly jet stream looks like a fairly quick response to the strat picture or am I missing something?