That's a very interesting and informative post, thanks. 🙂

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That's a very interesting and informative post, thanks. :)

Indeed.

Hopefully interesting times ahead.

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I agree with the science of chionomaniac1's post. The only caveat I would add is that this kind of pattern has occurred in January many times before and the changes that will occur in the circulation can readily produce a very mild second half to winter just as much as a cold one. Time will tell.

Interesting tweet from Joe ******i today

10mb warming on European over the pole by 360 hrs reaches 50C!!!! This is a huge event and will have N hemisphere cold implications

Interesting tweet from Joe ******i today

10mb warming on European over the pole by 360 hrs reaches 50C!!!! This is a huge event and will have N hemisphere cold implications

If it happens then cold where in the northern hemisphere could be the question?

Interesting tweet from Joe ******i today

10mb warming on European over the pole by 360 hrs reaches 50C!!!! This is a huge event and will have N hemisphere cold implications

If it happens then cold where in the northern hemisphere could be the question?

http://176.31.229.228/modeles/gfs/runs/gfsnh-2012010600-10-360.png?0

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Interesting tweet from Joe ******i today

10mb warming on European over the pole by 360 hrs reaches 50C!!!! This is a huge event and will have N hemisphere cold implications

If it happens then cold where in the northern hemisphere could be the question?

http://176.31.229.228/modeles/gfs/runs/gfsnh-2012010600-10-360.png?0

I'd assumed ******i would mean implications for cold lower down?

Many thanks to Chiono for an excellent post - much appreciated.
So Joe B is predicting the current rolling sequence to develop into a significant event? Be interesting to see how this progresses.

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http://wekuw.met.fu-berlin.de/~Aktuell/strat-www/wdiag/ts.php?plot=temps&alert=1&lng=eng 

A significant change overnight in the strat prediction model - sharp rise again due in the next few days.

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http://wekuw.met.fu-berlin.de/~Aktuell/strat-www/wdiag/ts.php?plot=temps&alert=1&lng=eng A significant change overnight in the strat prediction model - sharp rise again due in the next few days.

Yes - seems fairly typical that when one event has occurred, subsequent events are also triggered. Not sure what the relationship is, but in winters when we don't see an SSW, the profile remains flat, whereas in years when there is an SSW, it is generally followed by at least 2 or 3 subsequent events. Fingers crossed that it upsets the applecart and puts an end to our current spell of zonality.

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An SSW will show fairly shortly in the stratospheric models as a signal for the polar vortex to break down completely under the barrage of cumulative warmings caused by a wave breaking feedback already set up that will just keep gathering momentum.  After a brief quieter and more pleasant spell of weather next week, further very unsettled disturbed weather to endure for a couple of further weeks, but increasingly, especially in the north, a drop in temperature as the jet stream tilts NW-SE by the end of the month. Then, finally, low pressure will disrupt and slide south of the UK as arctic high pressure becomes dominant from the north in the next 4 to 5 weeks. So much colder conditions for Europe and our part of the world eventually arriving as a lagged tropospheric reponse to the complete changes in stratospheric pattern

An SSW will show fairly shortly in the stratospheric models as a signal for the polar vortex to break down completely under the barrage of cumulative warmings caused by a wave breaking feedback already set up that will just keep gathering momentum.  After a brief quieter and more pleasant spell of weather next week, further very unsettled disturbed weather to endure for a couple of further weeks, but increasingly, especially in the north, a drop in temperature as the jet stream tilts NW-SE by the end of the month. Then, finally, low pressure will disrupt and slide south of the UK as arctic high pressure becomes dominant from the north in the next 4 to 5 weeks. So much colder conditions for Europe and our part of the world eventually arriving as a lagged tropospheric reponse to the complete changes in stratospheric pattern

That's a very promising apprasail, I'll be living in hope then.

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An SSW will show fairly shortly in the stratospheric models as a signal for the polar vortex to break down completely under the barrage of cumulative warmings caused by a wave breaking feedback already set up that will just keep gathering momentum.  After a brief quieter and more pleasant spell of weather next week, further very unsettled disturbed weather to endure for a couple of further weeks, but increasingly, especially in the north, a drop in temperature as the jet stream tilts NW-SE by the end of the month. Then, finally, low pressure will disrupt and slide south of the UK as arctic high pressure becomes dominant from the north in the next 4 to 5 weeks. So much colder conditions for Europe and our part of the world eventually arriving as a lagged tropospheric reponse to the complete changes in stratospheric pattern

That's a very promising apprasail, I'll be living in hope then.

 

 I think there is every reason to believe it is one of the most likely routes that the rest of the winter will take. As ever though, time will tell

An SSW will show fairly shortly in the stratospheric models as a signal for the polar vortex to break down completely under the barrage of cumulative warmings caused by a wave breaking feedback already set up that will just keep gathering momentum.  After a brief quieter and more pleasant spell of weather next week, further very unsettled disturbed weather to endure for a couple of further weeks, but increasingly, especially in the north, a drop in temperature as the jet stream tilts NW-SE by the end of the month. Then, finally, low pressure will disrupt and slide south of the UK as arctic high pressure becomes dominant from the north in the next 4 to 5 weeks. So much colder conditions for Europe and our part of the world eventually arriving as a lagged tropospheric reponse to the complete changes in stratospheric pattern

That's a very promising apprasail, I'll be living in hope then.

 

 I think there is every reason to believe it is one of the most likely routes that the rest of the winter will take. As ever though, time will tell

 

Can't see it happening myself but it will certainly be interesting to watch if it does

Excellent Matt, thank you :)

Very positive developments today, shame about the lack of eye candy in the NWP, although clearly there is a notable time lag between events in the stratosphere and the troposphere.

I sense patience is wearing thin amongst many, but such is life! Here's hoping for real signs of cold soon, and please keep posting your analyses!

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Very very interesting post by Glacier Point on the other side. ;)

Some seem to think that a SSW is unlikely to be avoided given today's developments.

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Very very interesting post by Glacier Point on the other side. ;)

Some seem to think that a SSW is unlikely to be avoided given today's developments.

Indeed Joe, check the zonal wind forecast for the coming days

http://wekuw.met.fu-berlin.de/~Aktuell/strat-www/wdiag/figs/ecmwf1/fluxes.gif 

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Somebody may have already asked this before, but I've been wondering what the effect of the current cold stratospheric temperatures over the UK is - or are those temperatures 'normal' and hence the effect is neglible?

tia

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Somebody may have already asked this before, but I've been wondering what the effect of the current cold stratospheric temperatures over the UK is - or are those temperatures 'normal' and hence the effect is neglible?

tia

I think the extreme cold of the stratosphere in our neck of the woods is what is driving our terrible spell of zonal weather - without a significant SSW impacting on the vortex which is stuck in exactly the wrong place for us, we have no chance of a decent spell of winter weather.

Fingers crossed that the multiple SSWs are sufficient to break the vortex!

We need the Hammer of Thor to do its job!

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An SSW will show fairly shortly in the stratospheric models as a signal for the polar vortex to break down completely under the barrage of cumulative warmings caused by a wave breaking feedback already set up that will just keep gathering momentum. 

All that is needed now is for the updated forecasts to verify and we will have that SSW. In fact if the predictions verify, a few weeks down the line it could be quite a spectacular pattern change