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Stratosphere and Polar Vortex Watch


Paul

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Posted
  • Location: New Forest (Western)
  • Weather Preferences: Fascinated by extreme weather. Despise drizzle.
  • Location: New Forest (Western)

Agree with @Catacol. A reversal of the hemispheric mean is extremely rare and ironically the few observed cases have occurred mostly as a result of trop-driven major HLB scenarios of the most extreme kind (massive high across most of the Arctic) rather than a SSW.

Models are in the process of responding to a regional +ve GPH anomaly just N & NE of the UK. Not something they’ve done a great job at spotting very far in advance as usual. It’s actually taken off faster than I was anticipating yesterday such that the vortex drain from Canada not only looks more ‘segmented’ with smaller disturbances rather than one big low (which I did expect), but comes up against a lot more resistance than I’d been imagining we’d see before around 25th.

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Posted
  • Location: Wakefield, West Yorkshire
  • Location: Wakefield, West Yorkshire
17 hours ago, Bricriu said:

For blocking towards the end of the month and into February we need to be seeing signs of reversals first at 100 hPa, then at 200, 300 and finally 500 hPa levels, but they are absent.

How come no one has said this before now?

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Posted
  • Location: on a canal , probably near Northampton...
  • Weather Preferences: extremes n snow
  • Location: on a canal , probably near Northampton...
5 hours ago, Paul_1978 said:

How come no one has said this before now?

He just did....

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Posted
  • Location: Wakefield, West Yorkshire
  • Location: Wakefield, West Yorkshire
2 hours ago, Summer Sun said:

 

Are we thinking that the model output is not reflective of these changes yet then, and we should start seeing better charts in the very near future?

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Posted
  • Location: Longden, Shropshire
  • Location: Longden, Shropshire
1 minute ago, Paul_1978 said:

Are we thinking that the model output is not reflective of these changes yet then, and we should start seeing better charts in the very near future?

Who knows with this winter?!

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Posted
  • Location: st albans
  • Location: st albans

Ec 00z op run looks very different at 50hpa in the same way that the trop varies from the previous run - I am of the opinion that 50hpa op is a pretty poor forecast tool late on as it can often be skewed towards the trop output and be less consistent than the upper strat .... this run is skewed at 30hpa so lord knows what’s going on !!

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Posted
  • Location: Stoke Gifford, nr Bristol, SGlos
  • Location: Stoke Gifford, nr Bristol, SGlos
23 hours ago, Summer Sun said:

 

So yday this Metman tweets this and 24 hours later he helps pen their outlook which is a downgrade. Laughable!

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Posted
  • Location: Lincolnshire - 15m asl
  • Weather Preferences: Frost and snow. A quiet autumn day is also good.
  • Location: Lincolnshire - 15m asl
1 hour ago, Bristle boy said:

So yday this Metman tweets this and 24 hours later he helps pen their outlook which is a downgrade. Laughable!

Jumpimg in here - my daytime job away from the weather passion is as a historian trained in source evaluation, interpretations analysis and the art of communication. History is many things as a subject - but these are some of the more useful bits. The MetO are playing a game here where they need to ensure the outward facing media information is exactly what it should be - informative - but also fulfils the secondary (and nearly as important a role) of managing peoples' expectations. Anyone on here involved in management of change within an organisation will know exactly what I mean here - because stark statements are not only loaded with potential hyperbole when interpretated by others, but can also destabilise a situation. The third thing in the thinking will be that they dont want to be left with egg on face - though I hope this is very definitely third in the priority list.

So - you end up with statements that is more paradox than truth. To rate something at 25% and then follow it up with a "greater tan normal [chance] for an easterly" speaks a thousand words to me from the video posted a few up from here. The 25% will do a lot of temper anyone who might twitch - but the greater than normal chance probably reveals where their modelling actually is taking them. And while Marco probably feels more free to post his own views on his twitter feed, he must put the organisation first when writing for the Met - and that means other priorities.

It isn't laughable - it's the world of formal communications and organisational management. 

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Posted
  • Location: Stoke Gifford, nr Bristol, SGlos
  • Location: Stoke Gifford, nr Bristol, SGlos
4 minutes ago, Catacol said:

Jumpimg in here - my daytime job away from the weather passion is as a historian trained in source evaluation, interpretations analysis and the art of communication. History is many things as a subject - but these are some of the more useful bits. The MetO are playing a game here where they need to ensure the outward facing media information is exactly what it should be - informative - but also fulfils the secondary (and nearly as important a role) of managing peoples' expectations. Anyone on here involved in management of change within an organisation will know exactly what I mean here - because stark statements are not only loaded with potential hyperbole when interpretated by others, but can also destabilise a situation. The third thing in the thinking will be that they dont want to be left with egg on face - though I hope this is very definitely third in the priority list.

So - you end up with statements that is more paradox than truth. To rate something at 25% and then follow it up with a "greater tan normal [chance] for an easterly" speaks a thousand words to me from the video posted a few up from here. The 25% will do a lot of temper anyone who might twitch - but the greater than normal chance probably reveals where their modelling actually is taking them. And while Marco probably feels more free to post his own views on his twitter feed, he must put the organisation first when writing for the Met - and that means other priorities.

It isn't laughable - it's the world of formal communications and organisational management. 

And in large organisations there are usually comms gurus who oversee tweets that will become public. Those 'gurus' ensure any message is accurate and doesnt contain anything that is a misrepresentation or ambiguity. 

I used to work in Fin Servs and top management were only allowed company-monitored twitter accounts. I also know how big organisations operate in respect of comms. Regards

Edited by Bristle boy
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Posted
  • Location: st albans
  • Location: st albans
1 minute ago, Bristle boy said:

And in large organisations there are usually comms gurus who oversee tweets that will become public. Those 'gurus' ensure any message is accurate and doesnt contain anything that is a misrepresentation or ambiguity. 

I think they probably went with cost cutting .... if they ever existed ! 

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Posted
  • Location: st albans
  • Location: st albans

Ec op strat v similar to previous run and as you will see on Berlin in the morning, quite a change from previous guidance in the mid strat 

the more learned amongst us will no doubt comment on reasons for this tomorrow (if I didn’t know better I would almost say that it looks like the trop imprinting up into the strat but I doubt that’s likely .....)

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Posted
  • Location: Longden, Shropshire
  • Location: Longden, Shropshire
12 hours ago, bluearmy said:

Ec op strat v similar to previous run and as you will see on Berlin in the morning, quite a change from previous guidance in the mid strat 

the more learned amongst us will no doubt comment on reasons for this tomorrow (if I didn’t know better I would almost say that it looks like the trop imprinting up into the strat but I doubt that’s likely .....)

Is that for the better or worse for cold prospects?

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Posted
  • Location: New Forest (Western)
  • Weather Preferences: Fascinated by extreme weather. Despise drizzle.
  • Location: New Forest (Western)

Anyone else of the impression that we have the stratospheric anomalies downwelling but in such a diffuse manner that it's trop-led forcing that determines where the landing position of substantial +ve GPH anomalies is within a range spanning from NW to NNE of the UK?

The ECM runs of yesterday had a powerful trop-led 'opening of the door' just NW of the UK, offering one of the fastest possible routes to a cut-off HLB capable of sustaining for a long time.

The 00z ECM and GFS of today have ditched that in favour of the trop being less helpful, leaving the strat to do most of the work, which takes longer and establishes the main height rises N or NNE of the UK. Ensemble guidance appears to be split between this and something akin to the ECM runs of yesterday.

 

Let's see if the 00z ECM and GFS were just wobbling with respect to the trop-led ridge build in the mid-Atlantic. If so, it was a particularly big one! 

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6 hours ago, bluearmy said:

In a supposed downwelling environment up to 30hpa  ???

The nature of 'downwelling' has been described by a number of theories but whatever the downward influence on the troposphere doesn't alter the fact that the pattern of tropospheric heights will be always be seen in the stratosphere to some extent.

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Posted
  • Location: Camborne
  • Location: Camborne

Looking at the 70mb chart for T192, and the corresponding EPS mean for 500mb, to my untutored eye it still looks like the trop imprinting on the low strat so comments from those much more knowledgeable than I are welcome

2019011700_f192_70.nonenonehghtnonebrbk_nhem.gfs003.thumb.gif.008aa7698f8e99675baa0adfc5fdcf5c.gifindex.thumb.png.e676afcfae13897c3d49c29ce900eeda.png

Edited by knocker
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Posted
  • Location: New Forest (Western)
  • Weather Preferences: Fascinated by extreme weather. Despise drizzle.
  • Location: New Forest (Western)

The pattern at 70 mb has been propagating gradually downward within the stratosphere for a while, but there's some wave breaking taking place over the N. Atlantic too, so it could even be a combination of the two... though the stratosphere's probably leading the dance, so to speak, by allowing the initial ridge to build sufficiently for the trough off Canada to break against it.


This raises a big question - how come FV3 is still seeing things so differently? Scarcely any evidence of strat-trop interaction until the late stages of both the 00z and 06z runs today.

I know that once, it was being run without a full stratosphere coupled to it, but surely that's been added during the later stages of testing...? 

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Posted
  • Location: Saltdean,Nr Brighton,East Sussex,Hither Green,SE London.
  • Location: Saltdean,Nr Brighton,East Sussex,Hither Green,SE London.

Quick question for those with Knowledge on SSW events.

Given we seem to be on the cusp of a return to winter 'proper' and the clear evidence this time that the December strat event has played a part in where we are getting to, as was the case on two or three occasions in the last 10 years, did we have the same knowledge of these events twenty or thirty years ago.

There was a real lack of deep cold and  snowfall on this island of ours during the 90s and the early part of the 21st century, ( the so called modern winters!)did warmings take place? And if they did why no measurable effect on our climate? Were other drivers at play to stop anything notable occurring?

Edited by sunnijim
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Posted
  • Location: Wantage, Oxon
  • Weather Preferences: Hot, cold!
  • Location: Wantage, Oxon
2 hours ago, Singularity said:

The pattern at 70 mb has been propagating gradually downward within the stratosphere for a while, but there's some wave breaking taking place over the N. Atlantic too, so it could even be a combination of the two... though the stratosphere's probably leading the dance, so to speak, by allowing the initial ridge to build sufficiently for the trough off Canada to break against it.


This raises a big question - how come FV3 is still seeing things so differently? Scarcely any evidence of strat-trop interaction until the late stages of both the 00z and 06z runs today.

I know that once, it was being run without a full stratosphere coupled to it, but surely that's been added during the later stages of testing...? 

When it was announced that FV3 would replace the GFS, there were some PowerPoint presentations on its performance on the NOAA website.  Which, annoyingly, I now can't find (probably due to the shutdown).  Anyway, although in most areas performance was better than GFS, I'm pretty sure it said one area were it was poorer was in the stratosphere. 

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Posted
  • Location: Ramsey, Minnesota (USA)
  • Weather Preferences: Thunderstorms/Snow/Hail & Strong Winds
  • Location: Ramsey, Minnesota (USA)
17 minutes ago, Mike Poole said:

When it was announced that FV3 would replace the GFS, there were some PowerPoint presentations on its performance on the NOAA website.  Which, annoyingly, I now can't find (probably due to the shutdown).  Anyway, although in most areas performance was better than GFS, I'm pretty sure it said one area were it was poorer was in the stratosphere. 

Slide 51 comments on stratospheric errors  . 

 

Q3FY16GFSBriefingNCEPOD.pptx

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Posted
  • Location: Home :Peterborough Work : St Ives
  • Location: Home :Peterborough Work : St Ives

Also slide 47. The comment comes from Climate Prediction Center.

In addition to that the Space Weather Prediction Center also says it needs improvements in upper atmosphere

Have to say though that the endorsements from the Stakeholders is hardly compelling even though they all say Implement

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