Stratosphere temperature watch - 2016/17

[Nick F]

A fellow UK storm chaser, Pete Scott, who's in northern Norway, posted this photo he took of nacreous clouds today on fb:

 

 

[ArHu3]

5 hours ago, JeffC said:

in fact see this link - shows how it works... look at the flow in the different hemispheres - it reverses on the equator!

https://earth.nullschool.net/#current/wind/isobaric/10hPa/overlay=temp/orthographic=-34.68,-1.31,255/loc=-26.717,-0.805

 

 

There are 10 or so bigger and smaller vortices on the northern hemisphere , but none on the southern ? 

Edited January 28, 2017 by ArHu3

[Singularity]

1 hour ago, ArHu3 said:

how did the southern hemisphere end up with all easterlies!?

In summer the stratospheric flow reverses at 10 hPa due to solar input warmimg the temps and leading to a high centred near or over the pole.

The same process goes on in the N Hemisphere summer. I remember looking last August out of interest and there it was; a vast anticyclonic circulation. 

[snowbunting]

Wow.. where did that warming come from? That appeared out of slight warming. Given the timescale it has made an appearance at. Little wonder the models are chopping and changing. 

[Summer Sun]

 

[JeffC]

Not sure this is right , but at 10 hPa, spot temp is 9.9 deg C, that's a massive jump from yesterday!

https://earth.nullschool.net/#current/wind/isobaric/10hPa/overlay=temp/orthographic=-31.78,82.77,255/loc=94.518,65.876

 

 

[Allseasons-Si]

Oh!!!,here we go

10 & 30 hpa

 

[bluearmy]

2 hours ago, JeffC said:

Not sure this is right , but at 10 hPa, spot temp is 9.9 deg C, that's a massive jump from yesterday!

https://earth.nullschool.net/#current/wind/isobaric/10hPa/overlay=temp/orthographic=-31.78,82.77,255/loc=94.518,65.876

 

 

I can't find above zero jeff at 60N

the higher temps towards 65N 

looks bang in line with what the modelling shows (and showed leading up to it)

 

[JeffC]

59 minutes ago, bluearmy said:

I can't find above zero jeff at 60N

the higher temps towards 65N 

looks bang in line with what the modelling shows (and showed leading up to it)

 

Agreed BA, I was referring to the hotspot rather than along the 60N line. It is almost a jigsaw fit for the models.

Edited January 28, 2017 by JeffC

[Gael_Force]

9 minutes ago, JeffC said:

Agreed BA, I was referring to the hotspot rather than along the 60N line. It is almost a jigsaw fit for the models.

Derived from global models ...presumably GFS .... so one would expect a jigsaw fit. 

https://earth.nullschool.net/about.html

[JeffC]

1 hour ago, Gael_Force said:

Derived from global models ...presumably GFS .... so one would expect a jigsaw fit. 

https://earth.nullschool.net/about.html

yep does say GFS...well that explains that then!

[Summer Sun]

 

[Singularity]

2 hours ago, Summer Sun said:

 

It never ceases to irritate me how overly certain a lot of Twitter comments end up sounding. Hopefully it is just the character limit to blame!

Anyway - I wonder how their PV strength is calculated - is it focused on one level, several levels, or even consider the full structure? 

I'm pondering over this because recent GFS runs in the 12-16 day range have shown a stretched and not particularly vigorous vortex at 30 hPa for example (due to a bit of wave-2 action, albeit rather subtle).

[Weather-history]

What is the difference between a vortex sat over the polar with very cold air say -85C and a polar vortex sat over the pole with -50C air?

For instance does a polar vortex have a lower rotational speed with "warmer" air than with  colder air?

Edited January 28, 2017 by Weather-history

[chionomaniac]

2 minutes ago, Weather-history said:

What is the difference between a vortex sat over the polar with very cold air say -85C and a polar vortex sat over the pole with -50C air?

For instance does a polar vortex have a lower rotational speed with "warmer" air than with  colder air?

The u wind is dependent on the temperature differential between the polar stratosphere and the temp stratospherically at mid latitudes. So yes, the temperature is critically important.

[Weather-history]

2 minutes ago, chionomaniac said:

The u wind is dependent on the temperature differential between the polar stratosphere and the temp stratospherically at mid latitudes. So yes, the temperature is critically important.

Thank you

[Interitus]

3 hours ago, Singularity said:

It never ceases to irritate me how overly certain a lot of Twitter comments end up sounding. Hopefully it is just the character limit to blame!

Maybe, unfortunately posters in these fora don't have that excuse, lol

[Dennis]

looks like some will happen......needs some time 

[bluearmy]

Some interesting developments on the last two ec runs. Berlin charts reveal that the stretching of the strat vortex as illustrated by singularity results in the main part of the vortex residing over Canada at 150hpa  whilst higher up it's over ne scandi. (The vortex stretched across). you will have noticed the intesresting  part of the op run this morning and at 50hpa, there is indeed a split beginning to show 

a good trend towards a possible split in the mid/lower strat. and also note the latest ec op brings a further warming at day 10 into the equation. that does make me wonder if it is a reliable run.

  

 

  

[Summer Sun]

 

[bluearmy]

26 minutes ago, Summer Sun said:

 

a tech SSW reversal isn't required if the trop is making the running. As long as a strong reformed upper strat doesn't establish then a weak mid strat will allow some HLB to establish in the trop. A strong reversal would be great but it hasn't looked likely for a fair while now so hasn't been factored into any outlook. 

Edited January 29, 2017 by bluearmy

[chionomaniac]

3 minutes ago, bluearmy said:

a tech SSW reversal isn't required if the trop is making the running. As long as a strong reformed upper strat doesn't establish then a weak mid strat will allow some HLB to establish in the trop. A strong reversal would be great but it hasn't looked likely for a fair while now so hasn't been factored into any outlook. 

Exactly Nick. It is the combination of the wave 1 downwell and wave 2 upwell that will give us the best chance. That is why it really doesn't matter whether there is a technical reversal or not  at 10hPa - what is important has and is already occurring - the strat vortex is on the ropes and primed for an uppercut.....

[bluearmy]

GFS op is split right up to 5hpa by the end of the 12z op

Would be nice to see some consistency from each ECM later (especially as that would translate into the Berlin charts tomorrow morning  with all the extra stuff to see)

[chionomaniac]

14 minutes ago, bluearmy said:

GFS op is split right up to 5hpa by the end of the 12z op

Would be nice to see some consistency from each ECM later (especially as that would translate into the Berlin charts tomorrow morning  with all the extra stuff to see)

That would be as good as any wave 2 upwell. Promising.

[Singularity]

 

30 hPa just starts to feel the wave-2 from below at the end of higher-res and then it's all fine progress from there.

For once, almighty atmosphere, can a strong trend across multiple models please actually mean something rewarding? TIA