Stratosphere and Polar Vortex Watch 2020

[Griff]

10 hours ago, SqueakheartLW said:

Institute of meteorology charts for zonal winds clearly show up the stratospheric and tropospheric vortexes failing to couple to each other in the next 10 days

Latest

Day 1

Day 2

Day 3

Day 4

Day 5

Day 6

Day 7

Day 8

Day 9

Day 10

Even though the zonal winds go through the roof at 1hpa you will notice how little of the increase makes it below 50hpa and in fact the tropical jet stream stays consistent at around 30 m/s. The polar jet on these charts is so weak and displaced northwards on average and in fact around 60N near the surface we have average easterlies at times too. A significant sign of northern blocking setting up during this period but crucially for us, where in the N hemisphere is it going to set up

Also notice how the EQBO at 10hpa is beginning to link up to the forming anti vortex in the S Hemisphere. Wonder if this will give it a nice boost and help to push the WQBO lower down. Probably not much help for us this winter now but it could at least weaken the WQBO on average for this winter and set us up nicely with an established EQBO for next year, assuming we don't get another disruption event.

Talking more of the QBO it is now clear how much the new EQBO is building up at the 10 to 15hpa level but so far it has barely got any lower down and NASA Singapore site keeps switching between Westerly Phase and East, Descending Phase on this plot

It is clearer to see on this chart what progress has been made by the new EQBO. It has strengthen but so far has hardly descended but it appears it has started to get lower down to a small degree at least, too late now for this winter but maybe going to be of great help for next year

The MERRA chart shows that the EQBO has on average descended down and may be a more accurate chart since it is an average of the whole equatorial stratosphere rather than just the measurement above Singapore which is very likely to vary much more compared with the average situation. The strengthening of the EQBO shows up clearly on here and with the higher WQBO speeds descending on average we may see a 10+ figure for November QBO at 30hpa but I feel the December number is going to be lower based on what this chart is showing

I'd only be blatantly passing off the thoughts of others as my own, but a fair deal of chatter today indicating a strengthening strat PV but a disconnect with the SPV... Models still going for blocking with this month and next.

[bluearmy]

11 hours ago, SqueakheartLW said:

Institute of meteorology charts for zonal winds clearly show up the stratospheric and tropospheric vortexes failing to couple to each other in the next 10 days

Latest

Day 1

Day 2

Day 3

Day 4

Day 5

Day 6

Day 7

Day 8

Day 9

Day 10

Even though the zonal winds go through the roof at 1hpa you will notice how little of the increase makes it below 50hpa and in fact the tropical jet stream stays consistent at around 30 m/s. The polar jet on these charts is so weak and displaced northwards on average and in fact around 60N near the surface we have average easterlies at times too. A significant sign of northern blocking setting up during this period but crucially for us, where in the N hemisphere is it going to set up

Also notice how the EQBO at 10hpa is beginning to link up to the forming anti vortex in the S Hemisphere. Wonder if this will give it a nice boost and help to push the WQBO lower down. Probably not much help for us this winter now but it could at least weaken the WQBO on average for this winter and set us up nicely with an established EQBO for next year, assuming we don't get another disruption event.

Talking more of the QBO it is now clear how much the new EQBO is building up at the 10 to 15hpa level but so far it has barely got any lower down and NASA Singapore site keeps switching between Westerly Phase and East, Descending Phase on this plot

It is clearer to see on this chart what progress has been made by the new EQBO. It has strengthen but so far has hardly descended but it appears it has started to get lower down to a small degree at least, too late now for this winter but maybe going to be of great help for next year

The MERRA chart shows that the EQBO has on average descended down and may be a more accurate chart since it is an average of the whole equatorial stratosphere rather than just the measurement above Singapore which is very likely to vary much more compared with the average situation. The strengthening of the EQBO shows up clearly on here and with the higher WQBO speeds descending on average we may see a 10+ figure for November QBO at 30hpa but I feel the December number is going to be lower based on what this chart is showing

Those ec strat zonal flow charts are from the op so the  data close to the surface later in the run is going to be as unreliable as the op is - higher up the forecast data is likely to be more reliable though still not as much as ens data would be if we could see it 

[SqueakheartLW]

When looking at different layers of the polar atmosphere we can see varied stories in 10 days time

10hpa just looks terrible if you are hoping for any sustained cold weather in December

A totally compacted and cold vortex with very little sign of anything to disrupt this, even that small warm area isn't up to very much at all

1hpa is showing those rapid zonal winds but the temperature profile doesn't seem to match up with what is forecast

The cold temperatures appear to be scattered about in around 3 or 4 more pieces despite that strong vortex showing. Is something going on here that is going to disrupt the vortex?

150hpa is most interesting though

This shows the polar vortex in at least 3 different pieces in 10 days time with some warmer blobs mixed in too. Maybe not all bad news for December then with this lower section all in pieces

Also interesting wave 2 activity forecast to strengthen around days 8 to 10. Here are the day 10 charts

Look at that big up in activity at the top end of the stratosphere by day 10. Maybe this is the hope we need to disrupt that vortex before it does end up reaching polar vortex of doom status and a winter killer

At least there's no abnormal wave activity showing up near the equator to disrupt the descent of the new EQBO

Edited November 21, 2020 by SqueakheartLW

[northwestsnow]

^^

Thanks , lots going on up above and of course the oceans, Nina in particular..

 

[Duane S.]

ECM projects a further uptick in wave 2 activity as the first day of Meteorological winter arrives. Nothing spectacular in terms of intensity but early winter it is always good to see wave2 whilst the vortex is still in its building / fledgling state

Obviously it can never be taken in isolation but it often promotes vortex disruption/ split shortly afterwards.

[SqueakheartLW]

Looks like new EQBO is on the move downwards

Latest

Day 10

[northwestsnow]

41 minutes ago, SqueakheartLW said:

Looks like new EQBO is on the move downwards

Latest

Day 10

Preventing a coupling ? Or delaying at least?

[SqueakheartLW]

CFS wants to copy my opposite scenario to last year idea I posted the other day

My scenario                                                  Latest CFS runs

Notice both are crashing the vortex into near nothingness by January and all non bias corrected runs are getting to a reversal at some stage in January

Just hope it comes off as "Polar Vortex of Doom Part 2" isn't my idea of another winter down the drain

 

[snowking]

Unfortunately the bias corrected CFS outlook calls for far more average fare:

 

 

Of even more concern for me is the 10 day ECM forecast of the zonal wind cross section in the NH:

Whilst nothing too drastic just yet, clear signs there of some of the stronger zonal winds starting to imprint down closer towards the surface, with only really some minor Wave 2 closer to the top of the stratosphere attempting to make any sort of inroads on the beast aloft:

Of course all of that is still a forecast so we shall have to wait and see.

In the meantime I would be pinning my hopes far more on a bottom-up process to aid chances of some proper winter weather in the UK as opposed to anything aloft helping us for the foreseeable. 

[Griff]

Obviously a fair bit of excitement on the run up to December on the model thread, but surprised no one has posted yesterday's ecmwf....

Seems to suggest a fair bit of uncertainty and reason for interest.

[DavidS]

The below chart was posted on the model thread. I haven’t looked at the strat charts for a while. Will be interesting to see if the trend develops / strengthens.

[Seasonal Trim]

14 minutes ago, DavidS said:

The below chart was posted on the model thread. I haven’t looked at the strat charts for a while. Will be interesting to see if the trend develops / strengthens.

300+ Chart. Not falling for that one again!

[DavidS]

Just now, Wynter said:

300+ Chart. Not falling for that one again!

Yes it is a long way off. 

[Kirkcaldy Weather]

Was just about to mention as the gfs / GEFS have been picking up on warming starting at the later end of runs for a little bit now, we know sometimes they can be a little bit over eager with it but they did handle that Christmas warming of a few winters ago quite well IMO so let’s see how this plays out, a few charts to highlight the kind of thing that has been re appearing 

[Kirkcaldy Weather]

 

[Benny123]

 

[Griff]

On 24/11/2020 at 20:47, Griff said:

Obviously a fair bit of excitement on the run up to December on the model thread, but surprised no one has posted yesterday's ecmwf....

Seems to suggest a fair bit of uncertainty and reason for interest.

Surprised no one has posted today's ecm either... 

 

[Allseasons-Si]

 

[summer blizzard]

GFS is trying advertise a high amplitude 5/6 MJO orbit which is historically disruptive, that's probably why weakening is advised (though it actually needs to happen). 

[SqueakheartLW]

Looks like EQBO is finally on its way down

It is clear to see the general downwards trend here of both the new EQBO as well as that lingering WQBO. At the current rate we could be into an EQBO before the end of the winter with the general rate of descent at present although it is highly unlikely to have any impact on this winter now but could be perfect for next year as long as we don't get an early switch back to a WQBO before next winter

1 - When looking at the bigger view the descent is clear to see on here too and it has accelerated in recent times too. Also the speed of the EQBO at 10hpa has really picked up in recent times too, another sign that we are about to switch into an EQBO soon

2 - The WQBO has finally pushed all the way down to 100hpa and is now starting to show its effects below this. That could be bad for our winter prospects with effects of WQBO now appearing in the troposphere. I wonder if the QBO disruption events help bring on La Nina's as when the first one happened in 2016 we ended up with a weak La Nina event later in the year and after the event this year we have once again ended up with a La Nina, only a stronger one this time as the 2020 disruption was a bigger one

3 - Although the winds up from 6hpa and higher are westerly there is a clear sign here that they are starting to slow down a bit. Is this region going to be switching back easterly again soon. Also I have noticed the strange appearance of this chart with recent readings looking out of step with the past ones. I wonder if this is related to some upgrade they have had recently

Finally we are in the top left portion of this chart in the part where the new EQBO is appearing and starting to descend. Only as long as we get further than we did a year ago that is

When comparing the latest chart with the 10 day forecast chart you can see the clear further descent of the new EQBO. Another thing that sticks out to me is the weakening of the zonal winds above 60N by day 10 and also that small easterly wind low down at 60N too. Wonder if that is a northern blocking sign

[bluearmy]

3 hours ago, SqueakheartLW said:

 

When comparing the latest chart with the 10 day forecast chart you can see the clear further descent of the new EQBO. Another thing that sticks out to me is the weakening of the zonal winds above 60N by day 10 and also that small easterly wind low down at 60N too. Wonder if that is a northern blocking sign

You need to realise that the day 10 chart is the ec op which is below 50% accurate ......higher up in the strat it’s likely to be more accurate but below 100mb, it’s just reflecting the operational in the trop as already mentioned and any northern blocking sign is just as likely to be the op on an amplified wild goose chase 

[Snow lover 2020]

Even if we don’t get snow this month from these charts ! An SSW is developing which may give us a snowy January!  How is it looking folks? 

[feb1991blizzard]

3 minutes ago, Snow lover 2020 said:

Even if we don’t get snow this month from these charts ! An SSW is developing which may give us a snowy January!  How is it looking folks? 

Is it?

Edited November 30, 2020 by feb1991blizzard

[Snow lover 2020]

2 minutes ago, feb1991blizzard said:

Is it?

No an SSW has been talked about last few days. Where have you been? Lol it develops end of December 

[feb1991blizzard]

Just now, Snow lover 2020 said:

No an SSW has been talked about last few days. Where have you been? Lol it develops end of December 

More likely in mid to late Jan or even feb from where i ia coming from.