Stratosphere temperature watch - 2016/17

[sea swim]

hi Dennis, excuse my ignorance  but, how so? genuine question - and how might it impact please?

 

[Summer Sun]

Doubt this will impact the UK for a while should it happen

[AtlanticFlamethrower]

1.3 C

 

 

[bluearmy]

7 hours ago, Summer Sun said:

Doubt this will impact the UK for a while should it happen

Stewart's musings earlier re a potential disconnect relevant but even if that doesn't happen, the day 16 mean chart is going to be a little skewed by climatology and who knows where the actual centre will be and if it isn't just on its way to Canada. there is enough wave activity showing on the forecasts to keep the fella on his toes! 

[Paul_1978]

9 hours ago, AtlanticFlamethrower said:

1.3 C

 

 

Edited November 30, 2016 by Paul_1978

[Blessed Weather]

Dr Cohen with a couple of more positive tweets this afternoon. GEFS 11-15 day 10mb GPH & Temp anomaly "much warmer". And GFS forecast for poleward heat flux "something to watch".

[Singularity]

I wonder where that increased heat flux came from exactly in terms of the trigger; the GEFS plots for GLAAM and the MJO haven't changed much today.

Speaking of the MJO - once the interference to the signal from the Indian Ocean tropical cyclone has subsided, I wonder what the chances are that the plot will start to chase its own tail as a cycle unfolds similar to that last observed one? Though it may more more directly toward 5/6 (if perhaps rather slowly).

Just hit me that this thread is kind of a substitute for the technical discussion threads we used to have, thanks to how much tropical forcing and the GSDM link to stratospheric developments (both potential and observed).

[Dennis]

23 hours ago, sea swim said:

hi Dennis, excuse my ignorance  but, how so? genuine question - and how might it impact please?

 

Hi @sea swim;  its an SSW setup later - maybe this is a good point to have some nice PV disruptions in the diff layers of Hpa

Edited November 30, 2016 by Dennis

[sea swim]

14 minutes ago, Dennis said:

Hi @sea swim;  its an SSW setup later - maybe this is a good point to have some nice PV disruptions in the diff layers of Hpa

brilliant! thank you! (and hi!).

[bluearmy]

The zonal flow high up now takes on a more familiar vista for the time of year with the strongest winds moved from 40/50N as was the case through November to be at 60/70N 

Some impressive wave 2 temps as wave 1 subsides and now the attention moves to see whether that increased flow can work its way down through the strat at 60/70N or if a disconnect strat/trop establishes. 

[Duane S.]

BA beaten me to it in both cases, so here it is in pictures.

[lorenzo]

Equatorward EP Flux calming down a bit this morning...wave 2 uptick visible as per timeline plot.

[Singularity]

Is there an expectation that if Indo-Pacific tropical forcing plays out, the wave 2 attack on the vortex shown by current GEFS/GFS output will improve and manage to do more than just elongate the vortex in week 2? I've been trying to figure out how much the mid-late Dec potential relies on mid-lower stratospheric developments to back up those in the troposphere. Cheers!

Interestingly, even the lackluster attack currently shown by recent GFS runs still seems to hit the top of the vortex pretty hard;

 

Could we possibly cut off the vortex's legs and head? 

[Gael_Force]

The conundrum here is we have been told a chicken is going to hatch around the middle of December ..... problem, we are frantically searching for where the hen has hidden the nest and ... how many predators are closer to it than us.

[JeffC]

3 hours ago, Gael_Force said:

The conundrum here is we have been told a chicken is going to hatch around the middle of December ..... problem, we are frantically searching for where the hen has hidden the nest and ... how many predators are closer to it than us.

And is it a male or female chicken?!

[Interitus]

Those forecast wave 2 heights are not particularly impressive at this point, with 600 metres at 10 mb. For comparison, two close weak vortex analogue years of 2000/1 and 2009/10 both hit between 1600-1800 metres at a similar stage of the season.

[Gael_Force]

 

There's a higher than normal probability it will be a cock------------------up!

 

Edited December 1, 2016 by Gael_Force

[Interitus]

19 hours ago, Dennis said:

Hi @sea swim;  its an SSW setup later - maybe this is a good point to have some nice PV disruptions in the diff layers of Hpa

No, it shows the zonal stratospheric winds increasing between 70-90°N as the vortex moves over the pole.

[Dennis]

2 hours ago, Interitus said:

No, it shows the zonal stratospheric winds increasing between 70-90°N as the vortex moves over the pole.

Thnx at @Interitus lets see then what will build 

[bluearmy]

4 hours ago, Interitus said:

Those forecast wave 2 heights are not particularly impressive at this point, with 600 metres at 10 mb. For comparison, two close weak vortex analogue years of 2000/1 and 2009/10 both hit between 1600-1800 metres at a similar stage of the season.

Give it a chance !  It's only just getting going back end of the run. The n Pacific ridge seems likely to get closed off so maybe not likely to  become too large. 

[iapennell]

13 hours ago, s4lancia said:

BA beaten me to it in both cases, so here it is in pictures.

Interesting to note the Stratospheric(70 mb to 15 mb)) Westerlies high over the Equator and also between 150 and 300 mb in all tropical latitudes as well as the very strong Westerlies above 15 mb in the Arctic and sub-arctic Stratosphere. None of this portends anything like Sudden Stratospheric Warmings over the Arctic and the Westerlies high over the Equator show very clear the strong Westerly phase of the QBO, another indicator that this winter is unlikely to be a cold one in Britain.

The only straw at which cold-weather lovers could clutch is the strength of the Westerlies at the latitude and height of the northern Himalayas/Pamirs, which suggests that strong mountain torques could remove Westerly AAM from the Northern Hemisphere Circulation later this winter to permit greater scope for easterlies reaching the UK later. However, the subtropical jet-stream is not, if this illustration is anything to go by, either stronger than usual nor in lower latitudes/elevations than normal for the time of year- and it is that which would be required for big mountain torques removing Westerly AAM.

It looks like the Westerly AAM in the Northern hemisphere atmosphere is building up strongly and in the absence of a strong sink for this over mountains (or elsewhere) in lower latitudes it looks like higher latitudes are due for a resumption of the weather we would more normally associate with our winters in Britain,- i.e relatively mild and (at times) stormy.

[Summer Sun]

[northwestsnow]

3 minutes ago, Summer Sun said:

That looks utter carp for most of Europe! 

[Dennis]

2009 and 2016 

[bluearmy]

9 minutes ago, northwestsnow said:

That looks utter carp for most of Europe! 

That's the five day GEFS mean mid dec - not something we havent seen?