Stratosphere Temperature Watch 2012/2013

[chionomaniac]

Have any seasonals ever been right?

I hope not this time. It's hardly like they are all singing from the same sheet.

Back to the stratosphere today. And the ECM is still showing a cooling below average for this time of year. In fact the mean zonal winds are increasing and are edging ever closer to the troposphere.

This signal ( for an increased pv) is totally at odds with the ECM 32 dayer, metoffice 16+ dayer and GP - but not the ECM seasonal.

[chionomaniac]

Ps my info on the ECM seasonal update comes from the meteorologists on american wx

http://www.americanwx.com/bb/index.php/topic/34743-winter-2012-2013/page__st__2765#entry1857705

[Methuselah]

I hope not this time. It's hardly like they are all singing from the same sheet.

Back to the stratosphere today. And the ECM is still showing a cooling below average for this time of year. In fact the mean zonal winds are increasing and are edging ever closer to the troposphere.

This signal ( for an increased pv) is totally at odds with the ECM 32 dayer, metoffice 16+ dayer and GP - but not the ECM seasonal.

That's kind of what I was thinking, chio: signals - as per usual? - are so mixed, that the 'seasonals' cannot all be right. But they can, however, all be wrong...

[BLAST FROM THE PAST]

Are we coming to a test period? GP and MetO have their well respected ideas, the Stratos is pointing towards a developing PV as it continues to cool below average? I was really surprised at Helen Willetts' short video re cold end of month, not that because its against what I think BUT that they even made it this far out? Its great to see but I am surprised.

BFTP

[MR EXTREMES]

I think the increase in vortex strength is almost certainly going to put a spanner in the works for early winter.

I think mid December will see first signs of slowing vortex.

Jan Feb to be cold.

Now until then average and not settled.

Don't see a mild set up strat is not playing ball.

[bluearmy]

whilst the zonal winds are forecast to increase and slowly downwell, the direction of travel remains into our lattitude rather than the arctic. i would ignore the run past day 7 in the lower strat/ and trop as it is fi operational data which we wouldnt normally take too seriously.

[chionomaniac]

I have to say that I am really struggling with the idea of high latitude blocking that has been suggested for the end of the month. We are currently seeing a cooling of the stratosphere that at certain levels (such as 50 hPa) is close to record cold.

http://www.cpc.ncep....re/50mb9065.gif

Every level - right down to the troposphere - is showing dramatic cooling, and the mean zonal winds are reciprocally following suit.

Everything that I have learnt studying the stratosphere over the last five years will need to be thrown out of the window if high latitude blocking is to succeed in the coming weeks. If we see a dramatic change in the stratospheric conditions then perhaps I will reassess, but I just can't see any long term HLB's presently.

That is not to say that longwave patterns cannot exist under strong vortex conditions - but the likelihood is that these patterns will be quickly overcome by the strength of the vortex. If it wasn't for the -ve QBO I would be suggesting a vortex intensification period.

I really hope that I will be proved wrong and that for the first time we will see HLB's exist under cold stratospheric conditions because I would love to see a cold start to winter as we have witnessed in previous years.

I am still optimistic regarding later December and the rest of winter.

Edited November 9, 2012 by chionomaniac

[Chris D]

I have to say that I am really struggling with the idea of high latitude blocking that has been suggested for the end of the month. We are currently seeing a cooling of the stratosphere that at certain levels (such as 50 hPa) is close to record cold.

http://www.cpc.ncep....re/50mb9065.gif

Every level - right down to the troposphere - is showing dramatic cooling, and the mean zonal winds are reciprocally following suit.

Everything that I have learnt studying the stratosphere over the last five years will need to be thrown out of the window if high latitude blocking is to succeed in the coming weeks. If we see a dramatic change in the stratospheric conditions then perhaps I will reassess, but I just can't see any long term HLB's presently.

That is not to say that longwave patterns cannot exist under strong vortex conditions - but the likelihood is that these patterns will be quickly overcome by the strength of the vortex. If it wasn't for the -ve QBO I would be suggesting a vortex intensification period.

I really hope that I will be proved wrong and that for the first time we will see HLB's exist under cold stratospheric conditions becaused I would love to see a cold start to winter as we have witnessed in previous years.

I am still optimistic regarding later December and the rest of winter.

Wow well this is gonna turn very interesting...who will be right? Both sides of the argument seem to be very confident although I am confused as to what the Met O are seeing. Perhaps they are expecting some sort of Strat warming, even though its not seen by any of the models at the moment? That being said they will have access to some extra data surely?

Edited November 9, 2012 by Chris D

[phil nw.]

I tend to agree with your sentiments Ed and i posted as such some days ago when we could see the forecast increase of mean zonal winds starting to filter down.

We can only report what the models show and there does seem more Gef`s members showing a disorganised vortex at the 500hPa level in later frames.

If this does come off then it will have been a learning experience i guess..

[bluearmy]

but there could be an episode of HLB last week nov - surely the cold strat should not effect a response in the trop for approx 4 weeks from now which is beginning dec. i would suspect that a short period of HLB would not rewrite the rulebook but if the mid strat stays anomolously cold from now on and this HLB isnt blown away quite quickly, then all bets would indeed be off.

Edited November 9, 2012 by bluearmy

[Cloud 10]

....and yet we are still seeing charts like this from the ECM.

[bluearmy]

....and yet we are still seeing charts like this from the ECM.

but thats from fi which as we know is not good indicator of whats likely, especially in the trop. afaik there is no ens strat data to work from beyond day 7.

[bobbydog]

I have to say that I am really struggling with the idea of high latitude blocking that has been suggested for the end of the month. We are currently seeing a cooling of the stratosphere that at certain levels (such as 50 hPa) is close to record cold.

http://www.cpc.ncep....re/50mb9065.gif

Every level - right down to the troposphere - is showing dramatic cooling, and the mean zonal winds are reciprocally following suit.

Everything that I have learnt studying the stratosphere over the last five years will need to be thrown out of the window if high latitude blocking is to succeed in the coming weeks. If we see a dramatic change in the stratospheric conditions then perhaps I will reassess, but I just can't see any long term HLB's presently.

That is not to say that longwave patterns cannot exist under strong vortex conditions - but the likelihood is that these patterns will be quickly overcome by the strength of the vortex. If it wasn't for the -ve QBO I would be suggesting a vortex intensification period.

I really hope that I will be proved wrong and that for the first time we will see HLB's exist under cold stratospheric conditions becaused I would love to see a cold start to winter as we have witnessed in previous years.

I am still optimistic regarding later December and the rest of winter.

i think you are being a bit harsh on yourself there chio. for one, its not winter yet so you haven't been proved wrong. if we do get a cold winter with a cold strat, that doesn't mean you are wrong either. it adds another avenue to explore as to how and why this can happen. obviously there are other factors at play and the next mission would be to find out what conditions, or combination of, can override the strat.

it's certainly not a failing on your part, in fact it adds another tool to the box in understanding the complexities of the weather. keep up the good work!

[johnholmes]

Ps my info on the ECM seasonal update comes from the meteorologists on american wx

http://www.americanw...65#entry1857705

Its almost heartening to read and discover that site has nearly as many 'characters' shall I call them hoping not to give offence as we have on Net Wx!

[chionomaniac]

Its almost heartening to read and discover that site has nearly as many 'characters' shall I call them hoping not to give offence as we have on Net Wx!

Yes, and you get to know which ones to take notice of. For instance HM. He is also backing up GP's stance regarding the wave 2 pattern keeping the cold upper strat at bay into the start of December.

[lorenzo]

Great find with that thread C, HM is well switched on. ( They can keep the Hot Dog Smileys )..

PS - Also noticed that they too have a 'model bin' - must be an International thing to do with runs and forecasts.. !

Edited November 9, 2012 by lorenzo

[Cloud 10]

but thats from fi which as we know is not good indicator of whats likely, especially in the trop. afaik there is no ens strat data to work from beyond day 7.

Maybe been posted before,but interesting.

www.nws.noaa.gov/ost/climate/STIP/CTB-COLA/cristiana_091007.pdf

Ensemble forecasting in the stratosphere seems to be rather difficult.

[lorenzo]

Anything that brings in Eliassen - Palm Flux gets difficult !!

[Cloud 10]

Anything that brings in Eliassen - Palm Flux gets difficult !!

I wonder how long before we see the SEFS (Stratospheric Ensemble Forecast System) become available.

I have named it,just need someone to do the programming.

[bluearmy]

May not mean too much but the zonal wind at 30hpa failed to break 30m/s on yesterday's run - at least things aren't getting worse although the temp continues to stay cold.

not seeing the forecast beyond day 10 apart from 10hpa but I'm sure some helpful poster will let us know if the -80c and below now popping up in deep fi gfs is indicative of an even colder mid strat forecast in 2 weeks time?

[chionomaniac]

We have the first signs of an increase in wave 2 activity seen on the 10 day output. I think that it will be critical to see how strong this wave action is and how potentially this can disrupt the lower stratospheric and tropospheric pattern.

If it is weak then my suspicions are that the tropospheric corresponding pattern will be no more than a displaced Azores ridge that will topple. If the activity is strong enough then we could get a little bit more than that.

[bluearmy]

Ed, the sceuro/west Russian ridge is modelled to strengthen over the period and remain pretty well in situ - good place for it to be to drive those trop waves.

[Duane S.]

We have the first signs of an increase in wave 2 activity seen on the 10 day output. I think that it will be critical to see how strong this wave action is and how potentially this can disrupt the lower stratospheric and tropospheric pattern.

If it is weak then my suspicions are that the tropospheric corresponding pattern will be no more than a displaced Azores ridge that will topple. If the activity is strong enough then we could get a little bit more than that.

Regards wave 2 activity now showing up in the latest 10 day ECM, what should we be looking for (in terms of numbers / location) that you would class as weak (relatively ineffective) and strong (capable of upsetting the vortex) ?

[chionomaniac]

Regards wave 2 activity now showing up in the latest 10 day ECM, what should we be looking for (in terms of numbers / location) that you would class as weak (relatively ineffective) and strong (capable of upsetting the vortex) ?

With regards to geopotential height http://wekuw.met.fu-berlin.de/~Aktuell/strat-www/wdiag/eczm.php?alert=1&forecast=all&var=ha2&lng=eng - up over 750

[bluearmy]

I'm sure ed will update with a more technical take but to me, as the wave 2 activity picks up through the strat, the core of zonal wind strength appears to be headed further south in the strat. Caution as the most impressive numbers and forecast charts are in the latter time frames.

The result of all this seems to be a general steretchng of the strat vortex. Note that current 30hpa temps at the pole are at their lowest point below average so far this season and can't be that far off lowest recorded returns for the time of year.

Edited November 11, 2012 by bluearmy