Stratosphere and Polar Vortex Watch 2020

[jules216]

Some publications on Solar QBO relationship, good correlation with -QBO and solar flux below 80.

[Premiere Neige]

Watched the winter update on Gav's Weather Vids earlier. The ECMWF, UK Met and a German model whose name I forget all going for weaker than normal zonal winds for November, December and to a certain extent, January so you would assume they are sniffing an SSW early doors. Let's hope this continues and they're not barking up the wrong tree!

[Cheshire Freeze]

On 19/09/2021 at 20:35, Premier Neige said:

Watched the winter update on Gav's Weather Vids earlier. The ECMWF, UK Met and a German model whose name I forget all going for weaker than normal zonal winds for November, December and to a certain extent, January so you would assume they are sniffing an SSW early doors. Let's hope this continues and they're not barking up the wrong tree!

It's been looking like a very front loaded winter for a while now. In fact November looks the most conducive to blocking-

[damianslaw]

From memory there were quite a few calling last winter a front loaded one. Alas there was a SSW and we had cold some cold in the second half.. the locked in cold pattern came too late though in April. First half was quite cold, opened chilly in Dec and there was a 2-3 week cold period from Christmas to mid Jan. 

[Cheshire Freeze]

On 19/09/2021 at 21:21, damianslaw said:

From memory there were quite a few calling last winter a front loaded one. Alas there was a SSW and we had cold some cold in the second half.. the locked in cold pattern came too late though in April. First half was quite cold, opened chilly in Dec and there was a 2-3 week cold period from Christmas to mid Jan. 

Completely different set up to last year.

For starters this time last year we were in the embryonic stages of the broad pattern of Aleutian LP and Siberian/Russian heights. this manifested quite strongly through October. Still early but current ens guidance shows the opposite this year...more of an Aleutian HP if anything.

All seasonals I've looked at are going pretty strongly +NAO, especially into the latter half of winter- an example below.

My advice? Make the most of anything we get in Nov/Dec!

Edited September 19, 2021 by CreweCold

[Don]

32 minutes ago, CreweCold said:

My advice? Make the most of anything we get in Nov/Dec!

I’m starting to get the impression that you won’t be eating a sock this time if winter is mild overall, CC?!

[Cheshire Freeze]

On 19/09/2021 at 22:01, Don said:

I’m starting to get the impression that you won’t be eating a sock this time if winter is mild overall, CC?!

Things can change...early stages of thoughts at the moment sir! Mostly musing right now.

[Mike Poole]

1 hour ago, CreweCold said:

Completely different set up to last year.

For starters this time last year we were in the embryonic stages of the broad pattern of Aleutian LP and Siberian/Russian heights. this manifested quite strongly through October. Still early but current ens guidance shows the opposite this year...more of an Aleutian HP if anything.

All seasonals I've looked at are going pretty strongly +NAO, especially into the latter half of winter- an example below.

My advice? Make the most of anything we get in Nov/Dec!

Not sure what you are seeing there, today’s ECM T240 seems to have Aleutian low?

[damianslaw]

1 minute ago, Mike Poole said:

Not sure what you are seeing there, today’s ECM T240 seems to have Aleutian low?

NAO and AO forecast to go negative later part of the month which would signify propensity for northern blocking.. we shall see..

[Catacol]

An SSW in December would give us a chance of cold mid winter given lag. That's good enough for me as an appetiser though there is a very very very long way to go before any ECM sniff of a warm stratosphere translates into anything icy. And remember that an SSW can bring a wave 1 displacement that is unfavourable. If I'm honest I'm still smarting in irritation at last year when we were a whisker from a split and a properly cold mid winter and instead the vortex clung on and was displaced only...and the displacement just wouldn't quite sit right for us. A wave 2 split is much more likely to allow cold air to flood south.

Enjoyable early musings.

Edited September 20, 2021 by Catacol

[damianslaw]

15 minutes ago, Catacol said:

An SSW in December would give us a chance of cold mid winter given lag. That's good enough for me as an appetiser though there is a very very very long way to go before any ECM sniff of a warm stratosphere translates into anything icy. And remember that an SSW can bring a wave 1 displacement that is unfavourable. If I'm honest I'm still smarting in irritation at last year when we were a whisker from a split and a properly cold mid winter and instead the vortex clung on and was displaced only...and the displacement just wouldn't quite sit right for us. A wave 2 split is much more likely to allow cold air to flood south.

Enjoyable early musings.

Eventually we felt the full effect in April.. similar to 2013 with the very cold March.. long delayed reaction. Perhaps if one came in December, February would deliver..

[JeffC]

Imagining a La Nina front loaded winter, with the prospect of SSW Dec, so with fast trip response Jan & Feb delivering too...

[Cheshire Freeze]

At this point November is looking potentially well below average. Pretty much unanimous agreement of HP being situated somewhere in the N Atlantic. CFS strengthens the November signal

The issue with November is that it's a lottery as to whether we can get sufficient cold pooling to tap into.

Edited September 21, 2021 by CreweCold

[Gowon]

33 minutes ago, CreweCold said:

At this point November is looking potentially well below average. Pretty much unanimous agreement of HP being situated somewhere in the N Atlantic. CFS strengthens the November signal

The issue with November is that it's a lottery as to whether we can get sufficient cold pooling to tap into.

The core of the HP looks too far NW for me, CC.. We would probably end up with mostly South Westerly winds? 

[damianslaw]

43 minutes ago, CreweCold said:

At this point November is looking potentially well below average. Pretty much unanimous agreement of HP being situated somewhere in the N Atlantic. CFS strengthens the November signal

The issue with November is that it's a lottery as to whether we can get sufficient cold pooling to tap into.

Always nervous when we see early cold blocks in November. 2016 springs to mind and 2013 to an extent. Rather see a meridional flow with low heights on a NW-SE axis and heights building to the NE. On occasion such as 2009 we end up with a mild wet phase but crucially a blocked one still with trough coming unstuck. Either way I look for a trough scenario that struggles to make it to scandi... this has been the theme of 2021..

[Cheshire Freeze]

On 21/09/2021 at 18:32, D.V.R said:

The core of the HP looks too far NW for me, CC.. We would probably end up with mostly South Westerly winds? 

Looks like tentative signs of a UK/NW European trough to me...which could be cold if the dice land correctly. You could be correct for sure, but think it'd be worst case scenario in that general set up.

[Gowon]

31 minutes ago, CreweCold said:

Looks like tentative signs of a UK/NW European trough to me...which could be cold if the dice land correctly. You could be correct for sure, but think it'd be worst case scenario in that general set up.

In that case, I will be expecting the worse and hoping for the best 

[Methuselah]

1 minute ago, D.V.R said:

In that case, I will be expecting the worse and hoping for the best 

I see you're catching on? 

[Gowon]

Just now, Ed Stone said:

I see you're catching on? 

Been there, done that, got the T-shirt.

[jules216]

A lesson learned from past winters, always look to the East as much as North West, if you see SE Europe high joining across with NE Scandi and NE Russia then good luck sourcing cold pool. The worst case scenario is cool windy north westerly so the heating bills are huge but no snow with it. i am located in Slovakia and when I see people posting NAO charts like crazy but dont look East I get quite angry,like they never learn.

[Cheshire Freeze]

On 21/09/2021 at 20:01, jules216 said:

A lesson learned from past winters, always look to the East as much as North West, if you see SE Europe high joining across with NE Scandi and NE Russia then good luck sourcing cold pool. The worst case scenario is cool windy north westerly so the heating bills are huge but no snow with it. i am located in Slovakia and when I see people posting NAO charts like crazy but dont look East I get quite angry,like they never learn.

This one might be better for you?

[January Snowstorm]

There's a definite trend last few years of a very weak Atlantic. You get the feeling we came close to the jackpot last couple of years and it's only a matter of time. My one concern is a lack of proper cold, that even though the cards fall right it won't be cold enough! It can't be ignored that most proper cold last 10 years has been in situ in early Spring with Europe taking until post Christmas to cool down.

So for me plenty excitement ahead but we need to cold to build before any SSW hits...

[sebastiaan1973]

For the end of October. 

[northwestsnow]

6 minutes ago, sebastiaan1973 said:

For the end of October. 

[mountain shadow]

10 minutes ago, sebastiaan1973 said:

For the end of October. 

Yowzer!