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November 2013 achieved around 150 as solar flux. Seems to me this is high enough to consider solar max. Increased chance for stratospheric warming?

http://solarham.net/averages.htm

I have a guarded expectation for a SSW in Feb. Technically, the closer that the solar flux is to the higher cut off of 150, the better.

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Those Asian warmings high up in the strat continue to show in fi gfs. The 12z has a strong event at the end of the run which is significant (not the best word to use!) as it shows at 1hpa (strongest) and downwells to 10 hpa. It's a long way to the end of a gfs run but up till now there hasn't seemed to be as much co ordination as shows on this run. Just something to keep tabs on at this stage.

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Those Asian warmings high up in the strat continue to show in fi gfs. The 12z has a strong event at the end of the run which is significant (not the best word to use!) as it shows at 1hpa (strongest) and downwells to 10 hpa. It's a long way to the end of a gfs run but up till now there hasn't seemed to be as much co ordination as shows on this run. Just something to keep tabs on at this stage.

 

Another thing is the transition of the PV moving from Canada then Greenland which finally leaves it north of Scandinavia.

 

Obviously more runs need but always good to see.

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Another thing is the transition of the PV moving from Canada then Greenland which finally leaves it north of Scandinavia.

 

Obviously more runs need but always good to see.

 

sort of ends up svaalbard/ne greenland and stretched towards canada (where a large chunk would likely remain).  this new transfer of the parent vortex centre is now shown to be too close to greenland to allow any extension north of blocking. infact it also ties in with the uptick in the atlantic, (initially fuelled by the chunk of vortex near w greenland). we could well see a vigorous n arm during week 2.  to me, it doesnt look like it will be far enough ne to allow any atlantic height rises into greenland so the best we can hope for from a cold perspective would be a nw/se jet and some cool/cold zonality as we head towards the festive period. (should this vortex positioning verify)

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Haven't seen the strat time series for a while, be nice to have a crystal ball....

 

post-7292-0-83957800-1386456113_thumb.gipost-7292-0-51117500-1386456114_thumb.gi

 

Another way of looking at the Wave activity we keep searching for on the Berlin plots.

post-7292-0-25948900-1386456115_thumb.gi

 

OPI prediction

post-7292-0-23240000-1386456232_thumb.jp

 

A little more technical info on how the calculation is made ( helps if you have google translate..!)..

http://www.centrometeotoscana.it/forum/index.php?topic=7364.0

 

Very much reminds me of one of Ed's good analogies for things the one about dripping in oil, can't remember it all ! Gist being eventually the Wave 1 activity culminates to produce an effect.

 

Looking so far at the Wave 1 action on the plot above and comparing to the NWP Archive shows how important getting the blocking in the right place is.

 

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I've just been over to the Berlin site to try and find some positives from the latest ECM forecast. I struggled it's fair to say. We are staring down the barrel of what appears to be a very strong vortex setting up and dominating for a while. It's not often you see treble figures used in the zonal wind forecast, even if that is right at the top of the strat. Yes moderate wave 2 activity continues with a further bout forecast at D10 but unlikely to have much impact on the vortex. Once the ammunition runs out (aka pacific ridging downstream effects) the pv will be allowed to grow unabated, it will look to set up shop over its spiritual home near Greenland and run the show for quite a while.

Cold zonality is realistically our best bet for the foreseeable i suspect but i struggle to even see that with the predicted ao profile at present.

So on that cheery note lets hope the GFS is on to something with hints of warmings up above!

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The best 10mb chart of the winter so far.

 

Posted Image

 

Doubt it will come to much but this the nearest chart to those ones in late Dec last year, problem is though, these charts don't seem to sustain over the 4 runs like they did around late Dec last year, the temps nowhere near as high as last year but I thought I would throw it out there, I believe you don't actually need really high temps like close to freezing (correct me if im wrong) but you need the warmth to penetrate into the core of the vortex,

 

 

Its downwelling but not getting into the pole and disrupting the vortex, I suppose we need to give it chance though maybe on future runs.

 

Posted Image

Edited by feb1991blizzard

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It's a trend. The warming at the very top begins around day 10 now and then slowly works its way down. It seems to keep coming high up. At the moment, by T384, we are just about seeing the lowest temps displacing off the pole at 10hpa. nothing notable below this level at a high enough latitude. however, the vortex is strong so it will doubtless require sustained warmings high up to make a difference in the mid strat. a continued sceuro block will be a decent aid to wave activity if the ridging is far enough north. I recall similar set up last year or the one before. anyway, the forecast warming high up should be in the sights of ECM tomorrow.

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It's a trend. The warming at the very top begins around day 10 now and then slowly works its way down. It seems to keep coming high up. At the moment, by T384, we are just about seeing the lowest temps displacing off the pole at 10hpa. nothing notable below this level at a high enough latitude. however, the vortex is strong so it will doubtless require sustained warmings high up to make a difference in the mid strat. a continued sceuro block will be a decent aid to wave activity if the ridging is far enough north. I recall similar set up last year or the one before. anyway, the forecast warming high up should be in the sights of ECM tomorrow.

 

Problem is it may not last long before we go completely zonal.

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it would be great if someone somewhere could let us know if the ecm extended ens are seeing the same warmings at 1-10hpa that gfs seems to be (now that they go that high up).  also, are gefs seeing what gfs op is ?  

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it would be great if someone somewhere could let us know if the ecm extended ens are seeing the same warmings at 1-10hpa that gfs seems to be (now that they go that high up).  also, are gefs seeing what gfs op is ?  

 

EDIT: just looking  back on meteociel at those fi runs from mid dec last year that first showed the 10hpa warmings. the temps are quickly modelled to increase up to zero and above over n asia. at -30c, we are a fair way away from the kind of upper strat temps that did the damage a year ago.

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sort of ends up svaalbard/ne greenland and stretched towards canada (where a large chunk would likely remain).  this new transfer of the parent vortex centre is now shown to be too close to greenland to allow any extension north of blocking. infact it also ties in with the uptick in the atlantic, (initially fuelled by the chunk of vortex near w greenland). we could well see a vigorous n arm during week 2.  to me, it doesnt look like it will be far enough ne to allow any atlantic height rises into greenland so the best we can hope for from a cold perspective would be a nw/se jet and some cool/cold zonality as we head towards the festive period. (should this vortex positioning verify)

 

Yep - agree with all this. I see a cool zonal flow into Xmas week also as the vortex is shunted towards Svalbard by a combination of US and then Siberian warming. Height rises over the mid atlantic back on the agenda by then.

 

Experts please - ECM at about 192 today. Is the trough setup displayed there over the Himalayas and Tibet the sort of pattern we need to see a potential torque event? I'm reading up on these things when I can, and clearly the Rockies/Himalayas are the big players when it comes to a mountain forque event, but I'm a bit hazy on the sort of synoptic pattern that might be required. Here's the chart:

 

Posted Image

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Return to av MS. The coldest temps modelled to ease off the pole towards ne greeny. Nothing of note im afraid.

Thought as much, seems a decent spike upwards though.
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Looking at that chart, I would say you need just the opposite. High pressure right of the mountains, and low pressure left of the mountains, I think is the general "rule of thumb", with a huge number of variations of course. Posted Image

 

Best regards.

 

OK - I must be having a dull moment... or else my geography is way out. Does that chart not show low pressure to the left (west or upstream) of the mountains with higher pressure to the right (east)? Or by left and right do you mean north and south?

 

Can you be a bit more clear? And also if there are lots of variations to the "best" pressure pattern or synoptic pattern for such an event, is there somewhere I can go to read up on them? The papers that google throws at me are all very technical and I'm getting a bit more understanding of them... but they all seem to assume a knowledge of the synoptics required. Or perhaps they are just all written by scientists who dont have much of an interest in geography!!

 

This is the best bit of text I can find, relating to torques effects from the Alps and Massif Centrale in particular. States LP to the West of the event which is what I thought my posted chart suggested near the Himalayas in 8 days time. Interesting the bit about 4000m:

 

The torque analysis singles out eastward-moving large-scale systems. Their isobars are oriented from southwest (northwest) to northeast (southeast) near the mountain in zonal torque Tλ (Tφ) cases. The massifs tend to generate a low-level distortion of the pressure field such that the angular momentum of the flow over the mountain is reduced. These results can be explained within the framework of the scheme. The influence of the mountains on the pressure field is seen only at heights ≤4000 m. The low-level distortions of the pressure field contribute positively to the total torque for lags τ≤0 in the Alps and for all lags − 2≤τ≤2 days in Asia Minor, where only Tλ is evaluated. The impact of the Atlas mountains is seen only at Ï„ = 0. Copyright © 2008 Royal Meteorological Society

Edited by Catacol_Highlander

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EDIT: just looking  back on meteociel at those fi runs from mid dec last year that first showed the 10hpa warmings. the temps are quickly modelled to increase up to zero and above over n asia. at -30c, we are a fair way away from the kind of upper strat temps that did the damage a year ago.

 

On this day last year, the 384 chart was showing some warming; early days and no two events are identical, but we now know that these events can be modelled at long range.

Posted Image

 

 

Catacol, are we looking at heights? the anomaly version of the chart you posted.

 

Posted Image

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And straw clutch of the day comes from the ECMWF projected EP-Flux:

 

Posted Image

 

Look at that at day 10 - pointing very slightly polewards! Let's take a closer look at that in action:

 

post-1038-0-20049500-1386589036.png

 

A very benign but not hugely unexpected outlook both tropospherically and stratospherically at the moment - and I'm not personally expecting too much to change from that this side of January. I know Ed's own thoughts on the stratosphere differ slightly from this in terms of years, but the composite years from my own winter forecast for December give this at 30mb:

 

post-1038-0-37117400-1386589557_thumb.pn

 

Which bears reality when we take a look at the observed 30mb heights for the first 7 days of December so far:

 

post-1038-0-81569800-1386589387_thumb.gi

 

Similar to Ed my own composites (unsurprisingly as many of the years are the same) produce this for January and February:

 

post-1038-0-11397200-1386589449_thumb.pn

post-1038-0-12200400-1386589459_thumb.pn

 

Though when I break it down week by week the initial disturbance to the placement of the vortex looks likely to start during the second half of January.

 

So it's a case of repeating the message from all the way back at the start of autumn when we all began to look for signals for the upcoming winter - patience will be key.

 

SK

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On this day last year, the 384 chart was showing some warming; early days and no two events are identical, but we now know that these events can be modelled at long range.

Posted Image

 

 

Catacol, are we looking at heights? the anomaly version of the chart you posted.

 

Posted Image

 

no gael, the anomolys reflect heights in the trop. those temps are high up in the strat at 10 hpa. there is no real time correlation.

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So Snowking, it's by far to early to expect something from the stratosphere. All we can expect the next weeks is a strong polar vortex and perhaps some short NW-driven colder air.

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   no gael, the anomolys reflect heights in the trop. those temps are high up in the strat at 10 hpa. there is no real time correlation.

 

I think we are at cross purposes here - the anomalies chart was for the ECM 12Z ECM heights chart Catacol posted up the page - sometimes easier to see where the boundaries are on 'busy' NH charts.

Edited by Gael_Force

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OK - I must be having a dull moment... or else my geography is way out. Does that chart not show low pressure to the left (west or upstream) of the mountains with higher pressure to the right (east)? Or by left and right do you mean north and south?

 

Can you be a bit more clear? And also if there are lots of variations to the "best" pressure pattern or synoptic pattern for such an event, is there somewhere I can go to read up on them? The papers that google throws at me are all very technical and I'm getting a bit more understanding of them... but they all seem to assume a knowledge of the synoptics required. Or perhaps they are just all written by scientists who dont have much of an interest in geography!!

 

This is the best bit of text I can find, relating to torques effects from the Alps and Massif Centrale in particular. States LP to the West of the event which is what I thought my posted chart suggested near the Himalayas in 8 days time. Interesting the bit about 4000m:

 

 

Sadly I don't think you can find any explanations that are "user friendly". The topic itself is quite linked to heavy physics. The only way would be that some expert in this field can interpret the knowledge for you in a user friendly manner. 

 

But to answer you, even tho this is not really my field of expertise. Posted Image

 

I had my dull moment yesterday obviously, because I said left and right instead of west and east. You need high pressure east of the mountains and low pressure west of the mountains, for a MT event that we want to see.

Looking at your specific case: This is clearly one of the "many variations". Looking at some previous cases it actually does look semi favourable, now that I have actually rotate it for a better view. Posted Image I drew the ridge axis and trough axis.

 

Posted Image

 

North America on the other hand, is much more straight forward in being obviously less favourable, with clearly what you don't want to see for a favourable MT event. 

 

Posted Image

 

Just my two cents. 

 

Best regards.

Edited by Recretos
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