Stratosphere and Polar Vortex Watch 2020

[sebastiaan1973]

Update based on 12h of yesterday. We see downwelling for 10 days ahead, altough there is some 'resistance.' At day 9-10 we see an attempt to split the vortex. Around -10m/s at the these days.

[snowking]

The two 0z runs either side of the run above shown by @sebastiaan1973 also showing at least a partial split around day 10 - hopefully we continue to see continuity in this regard right down to T+0

 

[bluearmy]

4 minutes ago, snowking said:

The two 0z runs either side of the run above shown by @sebastiaan1973 also showing at least a partial split around day 10 - hopefully we continue to see continuity in this regard right down to T+0

 

My view of the ec op strat runs is that they are showing an effective split days 7/10 but no indication that it will sustain for v long and the Atlantic daughter doesn’t look to be in a great place for nw Europe. The gfs ops are showing the Asian displaced spv slowly edging towards the n Atlantic sector (scandi-Iceland) before a possible edge back to Asia again in week 3. 

It’s feasible that the ec could close the split and take the Atlantic daughter back into the Asian main. 

would love to see the eps (or even para) view of heights in the extended to get a handle on this. 

[northwestsnow]

I was just going to post something along those lines Blue.

The Atlantic sector continues to look poor from a trop POV.

[Monotone]

2 hafta sonra (yaklaşık) stratosferde meydana gelmesi muhtemel bir SSW, önce endekslere ve ardından GFS modeline yansıtıldı. Olası GGB'yi bir yapı olarak incelersek, bölüneceğini tahmin edebiliriz. Kutup girdabını parçalayan atımlar, Avrasya üzerinden ülkemize veya çevresine büyük bir sistem taşıyabilir.

 

Stratosferik bölgesel rüzgarlar, şekildeki gibi olası dönüşü ortaya koymaktadır. ECMWF ve GFS bu konuda hemfikir görünüyor. Bu, günler önce bahsettiğimiz Displace'den sonra Split'in olasılıklarını artırdı.

 

--- Forumunuzda yeniyim. Türkiye'den katılıyorum. Eleştiriye ve bilgiye açığım. teşekkür ederim"> 

EDIT: Translation using Google added:

An SSW likely to occur in the stratosphere after 2 weeks (approximately) was first reflected in the indices and then in the GFS model. If we examine the possible SSP as a structure, we can guess that it will be divided. The beats that break the polar vortex can carry a large system to our country or its surroundings through Eurasia.

Stratospheric regional winds reveal the possible turn as in the figure. ECMWF and GFS seem to agree on this. This increased the possibilities of Split after the Displace we mentioned days ago.

--- I'm new to your forum. I am joining from Turkey. I am open to criticism and information. thank you.

Edited January 7, 2021 by Blessed Weather
Translation added.

[SqueakheartLW]

GFS

GFS 00z and Parallel sticking to their guns with the possible 3rd warming

Looks like a further strengthening of the 3rd warming signal and a favourite temperature range is also starting to show itself now too

GFS and GFS Parallel Figures

                               00z         06z         12z         00z
Warming Peak     06/01     06/01     06/01     07/01
-28                         2             1             2              0
-24                         5             5             1              1
-20                         5             5             1              1
-16                         7             6             7              3
-12                         9             7             7              11
-8                           3             2              5              14
-4                           1             2              3              1
0                            1             3              5              2
+4                          0             2              2              0
Av Peak               -15.88    -13.45    -10.30      -10.30

Even though the average peak is the same as the last one the overall signal is stronger as we have lost more of the less warm peak options and at present it appears GFS is favouring a 3rd warming with a peak temperature close to -10C

GEFS Legacy

Even through I haven't posted the charts themselves this model is picking up on this 3rd warming too but isn't as keen as the GFS is on the peak of the warming or the damage it does to the vortex either

GEFS Legacy

Warming Peak     06/01     07/01
-32                         2             0
-28                         0             0
-24                         4             0
-20                         6             5
-16                         6             9
-12                         2             4
-8                           1             2
-4                           0             1
AV Peak               -19.43    -14.86

GEFS Legacy has strengthen its signal for a warming too but is still not as keen for this warming as the GFS is

[Bricriu]

I note a previous poster mentioned that with a displacement we are less likely to get a delayed spring, but if there is a third warming that might see off the Vortex, perhaps we will see a delayed spring afterall. I really would prefer if we got a proper cold spell in the heart of winter this time. Of course what i prefer means diddly squat.

 

Edited January 7, 2021 by Bricriu

[Blessed Weather]

2 hours ago, Monotone said:

2 hafta sonra (yaklaşık) stratosferde meydana gelmesi muhtemel bir SSW, önce endekslere ve ardından GFS modeline yansıtıldı. Olası GGB'yi bir yapı olarak incelersek, bölüneceğini tahmin edebiliriz. Kutup girdabını parçalayan atımlar, Avrasya üzerinden ülkemize veya çevresine büyük bir sistem taşıyabilir.

 

Stratosferik bölgesel rüzgarlar, şekildeki gibi olası dönüşü ortaya koymaktadır. ECMWF ve GFS bu konuda hemfikir görünüyor. Bu, günler önce bahsettiğimiz Displace'den sonra Split'in olasılıklarını artırdı.

 

--- Forumunuzda yeniyim. Türkiye'den katılıyorum. Eleştiriye ve bilgiye açığım. teşekkür ederim"> 

EDIT: Translation using Google added:

An SSW likely to occur in the stratosphere after 2 weeks (approximately) was first reflected in the indices and then in the GFS model. If we examine the possible SSP as a structure, we can guess that it will be divided. The beats that break the polar vortex can carry a large system to our country or its surroundings through Eurasia.

Stratospheric regional winds reveal the possible turn as in the figure. ECMWF and GFS seem to agree on this. This increased the possibilities of Split after the Displace we mentioned days ago.

--- I'm new to your forum. I am joining from Turkey. I am open to criticism and information. thank you.

Welcome to the forum Monotone. Unfortunately most folk on here wouldn't be able to read Turkish, so if you wouldn't mind, maybe you could do your own translation next time as your views are most welcome.  

[mushymanrob]

So what will the likely effects be of a second and third warming? further downwelling? a prolonged chance of a proper cold spell?  I dare say im not the only one who would like to know this... tia.

[Monotone]

1 hour ago, Blessed Weather said:

Monotone foruma hoş geldiniz. Maalesef buradaki çoğu insan Türkçe okuyamaz, bu yüzden sakıncası yoksa belki bir dahaki sefere kendi çevirinizi yapabilirsiniz, çünkü görüşleriniz çok hoş karşılanacaktır. "> 

I am sorry. 

I thought I was in the Turkish forum for a moment   I will share in english after that

[SqueakheartLW]

06z GFS runs and parallel still have the 3rd warming showing. Starting to look a more definite bet now but some of the runs are now showing a double hit warming so a big warmup, then a slight cooldown before another burst of warming shortly afterwards. I have put the double ones first followed by the single ones.

DOUBLE HIT 3RD WARMING OPTIONS

Parallel 06z GFS

06z Operational

Member 1

Member 2

Member 8

Member 9

Member 12

Member 14

Member 15

Member 16

Member 17

Member 18

Member 19

Member 21

Member 22

Member 24

Member 26

Member 29

Member 30

SINGLE 3RD WARMING OPTIONS

Member 3                                               Member 4                                                Member 5

Member 6                                               Member 7                                                Member 10

Member 11                                              Member 13                                             Member 20

Member 23                                             Member 25                                             Member 27

Member 28

Overall another boost to the warming signal and with 19 of the 33 runs showing the double hit warming then an even better signal overall showing now for a round of major warming later this month

The updated figures also reflect the further boost to the signal and in brackets next to the latest figures are the counts for the double hit peaks and the average peak warming for these too out of 19 options

GFS and GFS Parallel Figures

                               00z         06z         12z         00z         06z
Warming Peak     06/01     06/01     06/01     07/01     07/01
-28                         2             1             2              0             0 (0)
-24                         5             5             1              1             0 (3)
-20                         5             5             1              1             0 (4)
-16                         7             6             7              3             1 (1)
-12                         9             7             7              11           11 (2)
-8                           3             2              5              14          13 (5)
-4                           1             2              3              1             6 (1)
0                            1             3              5              2             1 (3)
+4                          0             2              2              0             0 (0)
Av Peak               -15.88    -13.45    -10.30      -10.30    -8.36

Double Hit Peak                                                               (-12.42)

Got the main 3rd warming average peak down below -10 now. This is starting to look like a major warming event and with 19 of those options showing another burst of warming just after the main event then this could be the final blow that sees the vortex destroyed

[chris55]

4 minutes ago, SqueakheartLW said:

06z GFS runs and parallel still have the 3rd warming showing. Starting to look a more definite bet now but some of the runs are now showing a double hit warming so a big warmup, then a slight cooldown before another burst of warming shortly afterwards. I have put the double ones first followed by the single ones.

DOUBLE HIT 3RD WARMING OPTIONS

Parallel 06z GFS

06z Operational

Member 1

Member 2

Member 8

Member 9

Member 12

Member 14

Member 15

Member 16

Member 17

Member 18

Member 19

Member 21

Member 22

Member 24

Member 26

Member 29

Member 30

SINGLE 3RD WARMING OPTIONS

Member 3                                               Member 4                                                Member 5

Member 6                                               Member 7                                                Member 10

Member 11                                              Member 13                                             Member 20

Member 23                                             Member 25                                             Member 27

Member 28

Overall another boost to the warming signal and with 19 of the 33 runs showing the double hit warming then an even better signal overall showing now for a round of major warming later this month

The updated figures also reflect the further boost to the signal and in brackets next to the latest figures are the counts for the double hit peaks and the average peak warming for these too out of 19 options

GFS and GFS Parallel Figures

                               00z         06z         12z         00z         06z
Warming Peak     06/01     06/01     06/01     07/01     07/01
-28                         2             1             2              0             0 (0)
-24                         5             5             1              1             0 (3)
-20                         5             5             1              1             0 (4)
-16                         7             6             7              3             1 (1)
-12                         9             7             7              11           11 (2)
-8                           3             2              5              14          13 (5)
-4                           1             2              3              1             6 (1)
0                            1             3              5              2             1 (3)
+4                          0             2              2              0             0 (0)
Av Peak               -15.88    -13.45    -10.30      -10.30    -8.36

Double Hit Peak                                                               (-12.42)

Got the main 3rd warming average peak down below -10 now. This is starting to look like a major warming event and with 19 of those options showing another burst of warming just after the main event then this could be the final blow that sees the vortex destroyed

Hi Squeak

Posting so many charts is making the thread really difficult to navigate on smartphones.

Maybe just put up a few examples to make the point?

But as you highlight the Strat is playing a big part this winter so lots to keep us interested going forward  

 

 

[Interitus]

9 minutes ago, SqueakheartLW said:

06z GFS runs and parallel still have the 3rd warming showing. Starting to look a more definite bet now but some of the runs are now showing a double hit warming so a big warmup, then a slight cooldown before another burst of warming shortly afterwards. I have put the double ones first followed by the single ones.

Got the main 3rd warming average peak down below -10 now. This is starting to look like a major warming event and with 19 of those options showing another burst of warming just after the main event then this could be the final blow that sees the vortex destroyed

Are they getting closer though? When consistently seeing peak warmings at 10 days or beyond they have a tendency to stay there, the strength of them doesn't matter so much.

[Eagle Eye]

Of course this SSW has a chance of bringing down the cold however looking at future charts it is unlikely that it'll happen in the way that we want it to. At the moment of course though that is too far away and could change butt everyone's eyes is on the SSW which has a chance even though it is seemingly relatively small of going off. So far the trend has been the best thing to get an idea of what is happening. 

For those wondering what a SSW is here is an explanation. 

A SSW or Sudden Stratospheric Warming occurs when the Polar Vortex winds keeping the extremely cold air over the Arctic that's in the Stratoshpere slow down and weaken this allows the cold air to collapse and become warmer rapidly. 

 

Over around a few weeks the Stratospheric air sometimes can come down and weaken the jet stream. This can block warmer air over the Atlantic and allow colder air to sink it's way down and envelop the UK and giving us a long spell of very cold air. 

 

If this happens and we get very cold air sinking that is most likely going to bring air from Arctic Areas which in turn could bring hefty Snow with it. 

 

It is easiest seen on the Jet Stream and Stratospheric Temperature Charts looking at ground temperature you should be able to see wether it has come down or not most likely. 

 

Forecasting these however can be hard and so it is most likely that you'll have to see what happens or look within the next few days and see how well further outlooks stick with further runs. 

The Stratoshpere towards Arctic Region has warmed up certainly.

Sorry if this bit should be in another thread. 

At the moment towards the end after this high. 

It seems expected that the Arctic Air will sink but this is very far out and is unlikely to happen. 

The Stratoshpere this Winter has been the main focus. 

I hope it does come of though becuase it should still be there on the 24th if it does come off and I'll have Snow on my Birthday for the first time in Year's perhaps Even The first time .

I am an Enthusiast so I Warn you to take my Posts as I mean them to be with a Pinch of salt. 

Xander

[bluearmy]

29 minutes ago, Interitus said:

Are they getting closer though? When consistently seeing peak warmings at 10 days or beyond they have a tendency to stay there, the strength of them doesn't matter so much.

Well one just did ! 

[Interitus]

44 minutes ago, bluearmy said:

Well one just did ! 

Current events notwithstanding,  for example here is a chart of forecasts over a few days last winter, inside 9-10 days the windspeeds progressed forward from run to run, at around 9-10 days they clustered without progressing, and beyond that they diverged all over the place -

Of course not forgetting previous GEFS tendency to overcook wind reduction compared to GFS, here again from a portion of last winter, a day-10 comparison -

Edited January 7, 2021 by Interitus

[bluearmy]

4 minutes ago, Interitus said:

Current events notwithstanding,  for example here is a chart of forecasts over a few days last winter, inside 9-10 days the windspeeds progressed forward from run to run, at around 9-10 days they clustered without progressing, and beyond that they diverged all over the place -

Of course not forgetting previous GEFS tendency to overcook wind reduction compared to GFS, here again from a portion of last winter, a day-10 comparison -

We have a new gefs this winter I think. Anecdotally they seem to have wanted to increase the zonal 10hpa too quickly !  Could be my mind playing tricks though .....

[ALL ABOARD]

3 hours ago, Interitus said:

Are they getting closer though? When consistently seeing peak warmings at 10 days or beyond they have a tendency to stay there, the strength of them doesn't matter so much.

Do they? 

GFS picked this SSW at 384 hours.... 

And was first not to model a full split. 

 

[Don]

4 hours ago, mushymanrob said:

So what will the likely effects be of a second and third warming? further downwelling? a prolonged chance of a proper cold spell?  I dare say im not the only one who would like to know this... tia.

Well, I haven't a scooby, except the the more warmings, the higher the chance of the PV becoming shredded, increasing the chance of cold to our shores?

[Vikos]

In all those 3rd warming charts, I only see minor warmings wich in most cases don't tend to affect lower regions of strato or even troposphere regions. correct me if i am wrong. And a SSW is always declared as a full SSW (per definition) after verifications of a lot of different parameters, not only 10hpa wind reversal (f.e. ozone concentration and stuff...).

[sebastiaan1973]

39 minutes ago, Vikos said:

In all those 3rd warming charts, I only see minor warmings wich in most cases don't tend to affect lower regions of strato or even troposphere regions. correct me if i am wrong. And a SSW is always declared as a full SSW (per definition) after verifications of a lot of different parameters, not only 10hpa wind reversal (f.e. ozone concentration and stuff...).

What is a full SSW?

[Interitus]

1 hour ago, ALL ABOARD said:

Do they? 

GFS picked this SSW at 384 hours.... 

And was first not to model a full split. 

 

Yes, they do!

It may well have picked it at 384, it will also falsely pick many others that don't materialise.....

[Vikos]

32 minutes ago, sebastiaan1973 said:

What is a full SSW?

All parameters fullfiled. Not only tempraise and zonal wind change. There are a few...

[sebastiaan1973]

3 minutes ago, Vikos said:

All parameters fullfiled. Not only tempraise and zonal wind change. There are a few...

Never heard of. Do you have a paper/ article for this?

[Vikos]

41 minutes ago, sebastiaan1973 said:

Never heard of. Do you have a paper/ article for this?

Maybe I tried to explain it to simple, due my bad english. I am trying again

In the SSW, which only means: rapid stratospheric warming, it is the case that this rapid warming must take place with both results (minor or major warming). In this respect, a SSW is "neutral" and initially open-ended. Right now we had a rapid warming in the stratosphere and above that, in the mesosphere. The heat is then transferred downwards in bursts, i.e. with heat peaks. However, this also requires increased ozone levels in the right places. In part, these result from warming, as the heat turbulence whirls the air layers upside down and ozone is transported into other air layers. This consequently means that the current state of the ozone concentration cannot be named one-to-one as a future indicator of successful warming as an argument of exclusion. The layers of air interact with each other as soon as there is unrest in the layers (vertical movements). So, to see if a real/full SSW-MajorWarming or just a very strong minor warming occured, one have to check (in the aftermath) the ozone levels before and after.
 

What we all want isn't only a SSW (this happens couple of times stronger or weaker in winter), but a MAJOR WARMING as an effect of the SSW.

The study by Karphechko et al. (2017) came to the conclusion that 43% of ALL SSWs are to be classified as so-called "non-downward propagating SSWs" - that is, quasi SSWs without any effects on the troposphere.

More about ozone and SSW here

Response of Arctic ozone to sudden stratospheric warmings

ACP.COPERNICUS.ORG

---

<p><strong>Abstract.</strong> Sudden stratospheric warmings (SSWs) are the main source of intra-seasonal and interannual variability in the extratropical stratosphere. The profound alterations to the...

Have a look at 30hpa, there is a tiny tiny reversal, and its the only chart of the ten to show a minus.

 

Edited January 7, 2021 by Vikos