Winter 2012 / 2013 Part 3

[philglossop]

Here in lies the problem. The so called classic months of January 2010 and December 2010 simply weren't that good snow wise down here. With regards to January 2010 we had a morning of snow which melted quickly. December 2010 was cold and we had a amount of snow around the night of the 19th December which froze and thus lingered past Christmas, but simply there wasn't a "dumping" of snow like the rest of the country. If you look at that now famous sat image of the UK covered in snow guess which bits of the country are still green- most of Cornwall and an arc around Plymouth.

So what does this mean for this winter coming? Absolutely nothing- other than statistically we are well over due our turn. The last time we had snow comparable to the winter of 09/10 and Dec 10 was January 1987. Yes we've had some snow events here in the intervening years (1994 comes to mind), but nothing major.

I'm with Kevin weather wise for this winter- we're overdue a Scandi High and a channel low (1979). Will it happen for us this winter I wonder.

[Buzz]

Every model and every forecast aren't fool proof otherwise dismiss everything else and just go with the one that is right all the time. They are indicators to potential and nothing more. I have to say, all this arguing, not discussion is getting a bit tedious. Why do you not have one to one disagreements so that we do not need to read through loads of point scoring posts?

Well said.

You know they say that Christmas gets earlier every year? Well, so does the petty bickering on this forum.

[chionomaniac]

I apologise and will leave it there

[bluearmy]

i was thinking ref 2010 re naefs but i wasnt wrong in recalling that 2009 was not a surprise. according to the strat thread linked to, ed posted on the 1st of dec that an alaskan height rise was likely and a looking through the archived ncep pattern for mid december, it is indeed a large alaskan height rise that triggers the downstream reversal of the AO, retrogression of a n european block and delivers the cold to our shores. i assume exeter were looking at the same strat info as chio through the latter part of november and this, together with a favourable ecm 32 day forecast led to their good forecasts for the second half of december.

[bobbydog]

No I can assure you it wasn't my intention and I should of worded my post differently. I shall continue to follow the stratosphere thread avidly this winter but I remain rather sceptical. Im not sceptical of how influencial the stratosphere is but rather our understanding.

is it really a lack of understanding? or an unexpected change in teleconnections, over-riding the expected scenario?

we do understand that this can happen.

[Methuselah]

Every model and every forecast aren't fool proof otherwise dismiss everything else and just go with the one that is right all the time. They are indicators to potential and nothing more. I have to say, all this arguing, not discussion is getting a bit tedious. Why do you not have one to one disagreements so that we do not need to read through loads of point scoring posts?

So, who would that be? I've never, ever come across a forecaster whose forecasts are anywhere near 'right all the time', despite what a few of them claim in their pathetic attempts at self-verification/justification (if dates are impossible to define, why define them?)...

The various indices and anomalies are nothing more than indicators; they are not forecasts. And, I think it's reasonably fair to say that the early indications (2009) were for a colder than average winter? I was wrong, in 2009, in that I was over-sceptical of the work then being done on Strat temps...

So, this time, I'll remain more open-minded!

[bobbydog]

Hmmmmm

http://www.dailymail...t-prove-it.html

interesting. this 'global warming pause' is not being denied. (played down as temporary by some)

got me thinking again though, 16 years?

[johnholmes]

i was thinking ref 2010 re naefs but i wasnt wrong in recalling that 2009 was not a surprise. according to the strat thread linked to, ed posted on the 1st of dec that an alaskan height rise was likely and a looking through the archived ncep pattern for mid december, it is indeed a large alaskan height rise that triggers the downstream reversal of the AO, retrogression of a n european block and delivers the cold to our shores. i assume exeter were looking at the same strat info as chio through the latter part of november and this, together with a favourable ecm 32 day forecast led to their good forecasts for the second half of december.

both 2009 and 2010 were fairly well predicted as far as I recall, sadly I can't find either my T+240 checks I ran for many many months nor my own saved files on 30mb warmings. I'll keep searching though.

[EML Network]

The -ve PDO has weakened substantially since summer, as has the cool SST pool to our north.

ENSO looking more like La Nina then El Nino at the moment.

I believe that there is some warmer up welling due along the Western Pacific see image below...that in turn would prevent a La Nina developing there is also a small pool of colder water in the subsurface anomaly chart, which is currently where we already have a negative anomaly at the surface , so looking ahead I would estimate were likely to see ENSO neutral conditions until the end of the year, possibly strengthening into above +0.5 in January 2013 which as I am sure you know is the thresh hold for El Nino conditions

[Gavin P]

Hi all,

Here's my third winter round-up. Once again looking at SST's, ENSO, snow cover and other things besides;

http://www.gavsweathervids.com/seasonal.html

Things seem to be progressing quite nicely.

Enjoy

Edited October 14, 2012 by Gavin P

[Severe Siberian icy blast]

Here in lies the problem. The so called classic months of January 2010 and December 2010 simply weren't that good snow wise down here. With regards to January 2010 we had a morning of snow which melted quickly. December 2010 was cold and we had a amount of snow around the night of the 19th December which froze and thus lingered past Christmas, but simply there wasn't a "dumping" of snow like the rest of the country. If you look at that now famous sat image of the UK covered in snow guess which bits of the country are still green- most of Cornwall and an arc around Plymouth.

So what does this mean for this winter coming? Absolutely nothing- other than statistically we are well over due our turn. The last time we had snow comparable to the winter of 09/10 and Dec 10 was January 1987. Yes we've had some snow events here in the intervening years (1994 comes to mind), but nothing major.

I'm with Kevin weather wise for this winter- we're overdue a Scandi High and a channel low (1979). Will it happen for us this winter I wonder.

To be honest I think the problem for you is your location,if 1987 was the last time you had a winter close to 2010 then you can see how sparse winters really are on the south coast. Do what I did , and move to higher ground if your not getting any. I'm much happier these winters!!

[Catacol]

Actually my comments were not factually incorrect. I recall Dec 2009 vividly because the Met O were predicting that cold spell weeks in advance during the 30 day forecast update. I remember many of us were puzzled because what they were forecasting was not being indicated by the models.

Sorry - I want to post one final comment on this. A couple of pages back you wrote this:

"If we look back at recent winters I can find quiet a few examples of how we need to understand the variables that dictate our climate. For example I revisited the thread after the Dec 2009 cold spell and even just 2 weeks away prior to the cold spell arriving nobody saw that cold spell coming."

I have just popped back to the old strat thread myself from November 2009 and there are multiple comments from the first week in November from CH referring to a Canadian warming and a disruption to the vortex. This key post from GP then appeared on 21st Nov:

"With the tropical stratosphere cooling again, this should strengthen ozone concentrations over the Arctic into late December.

A couple of things are very evident looking at these comparisons:

1) The polar vortex will be weaker than any other winter this decade.

2) The position of the ozone concentration has been consistently building over the Pacific. These drift east over time. This means that the most likely place for the warming (and tropospheric impacts) look like starting over the Canadan Arctic and migrating eastwards towards Greenland with a trough over Scandinavia and western Russia."

Note that last comment: a trough over Scandinavia and Western Russia. This was a product directly of the Canadian warming that was discussed for 3 weeks prior to this post. That is exactly what we got, with the segment of the vortex that so famously now dropped over us.

So - I reiterate my initial point : if you are going to state something that is palpably wrong, and potentially misleading to new members of the forum, then be prepared to take the flak. SSW may not be absolutely the holy grail of forecasting, but it is a very strong indicator, and the fact that the MetO have so publically made it clear that their latest long range model now takes account of stratospheric signals would suggest that paid professionals are on the same wavelength too.

Edited October 14, 2012 by Catacol_Highlander

[weather is fun]

Im not been funny here but it seems to be that the signs for a milder than average winter are once again looking likely or have i got the wrong end of the stick?

[liam79]

Im not been funny here but it seems to be that the signs for a milder than average winter are once again looking likely or have i got the wrong end of the stick?

Nobody knows really at this range, but the chances are the same as before IMO.

[Relativistic]

Does the -PDO factor into that forecast?

Yes, previous analogues of the PDO show all of the aformentioned happening.

[TEITS]

You keep mentioning this, but in 2009 we were getting to grips with some of the stratospheric connections. The early November stratospheric warming was well documented leading up to this type of post on Dec 1st 2009.

http://forum.netweat...20#entry1624425

To suggest that it wasn't spotted is misleading at best.

if you're going to highlight posts then what about this on the 11th Dec.

"I am not as convinced as I was a couple of days ago that the current increased forecast wave 2 activity is going to lead to anything. Hopefully it will, but I am beginning to see signs in the forecasts that the stratospheric vortex is regrouping and regaining strength. Both the ECM and GFS suggest this with no significant warming on the horizon"

http://forum.netweat...h/page__st__180

When you read the posts around this period many posts are still searching for signs of a SSW. The Dec 2009 cold spell occured due to a split vortex but from what I can tell no SSW occured prior to this, only minor warmings.

Just add Jan 2010 was the coldest since 1987 despite your comments about "no significant warming on the horizon".

Edited October 14, 2012 by THE EYE IN THE SKY

[Polar Maritime]

Im not been funny here but it seems to be that the signs for a milder than average winter are once again looking likely or have i got the wrong end of the stick?

Until November at the earliest, signal's will flip/flop. Nothing is set in stone, with 7 weeks to go until the start of Winter... !

It's interesting watching the models/members struggling at this range, jumping on to any band wagon that expresses what they want.

Patience is virtue.

Edited October 14, 2012 by Polar Maritime

[bluearmy]

Was there a SSW in late 2010. Don't think so. The split vortex was a consequence of strat patterns but there was no SSW, just warmings lower down that caused the tropospheric split. Remember a SSW is a reversal of mean zonal winds at 30 hpa. By the 11th of dec, the cold spell was well trailed by the models. NOAA cpc first showed it on 4th December 10/14 dayer. I suppose ed was looking beyond the cold spell by then for what might follow in January.

[January Snowstorm]

I think that was 2010 BA. During 2009 the GFS did consistently model a GH but that was around the +240 mark. What was startling at the time is how the Met O predicted the Dec 2009 cold spell back in late Nov and they consistently went with this forecast.

Indeed they really did exceptional for that cold spell and it's very clear to me that they must have much more access to charts etc than we have or else know better how to analysis them in depth. Else of course they could have just got lucky.

Overall though I think their long term forecasts are very important in the overall scheme of things!

[Catacol]

if you're going to highlight posts then what about this on the 11th Dec.

"I am not as convinced as I was a couple of days ago that the current increased forecast wave 2 activity is going to lead to anything. Hopefully it will, but I am beginning to see signs in the forecasts that the stratospheric vortex is regrouping and regaining strength. Both the ECM and GFS suggest this with no significant warming on the horizon"

http://forum.netweat...h/page__st__180

When you read the posts around this period many posts are still searching for signs of a SSW. The Dec 2009 cold spell occured due to a split vortex but from what I can tell no SSW occured prior to this, only minor warmings.

Just add Jan 2010 was the coldest since 1987 despite your comments about "no significant warming on the horizon".

Sorry TEITS - but you are not going to win this argument by cherry picking one post out of lots and lots that stops to raise a doubt over the impact of wave activity. Jan 10 was indeed cold overall, but the vortex was reforming throughout January and eventually the cold weather passed as the month progressed. This is exactly what CH begins to refer to in posts in the latter half of Dec 10 and, once again, it came true.

You have simply reinforced the argument that strat effects can often be directly linked to troposheric impacts by highlighting this post.

Let's remember throughout this running debate that strat experts always tell us that troposheric impacts are time lagged by about 4 weeks give or take.

[BornFromTheVoid]

I believe that there is some warmer up welling due along the Western Pacific see image below...that in turn would prevent a La Nina developing there is also a small pool of colder water in the subsurface anomaly chart, which is currently where we already have a negative anomaly at the surface , so looking ahead I would estimate were likely to see ENSO neutral conditions until the end of the year, possibly strengthening into above +0.5 in January 2013 which as I am sure you know is the thresh hold for El Nino conditions

True that the particular area near the dateline has warmed a little, but if we look at the progression of the last few weeks

We can see how rapidly the rest of the sub surface +ve anomalies have disappeared and even reversed. Therefor, I would be doubtful as to whether we'll see any strengthening at the surface before the end of the year

http://www.cpc.ncep....s-fcsts-web.pdf

[A.J]

Just wondering if there's any chance of discussion on the Winter of 2012/13 as per the thread title, as I've just wasted 30 minutes of my life reading post after post of 'My dads better than your dad' point scoring rubbish. Sorry chaps, but agree to disagree and move on, or start your own relevant threads/PM's but to be honest I'm sure I'm not the only member who's fed up to the back teeth of these off-topic arguments...Can't we just talk about the forthcoming winter and just all get along?......cheers

[johnholmes]

After much searching I finally found the 30mb temperature curve 2009-2010

sorry its small but it does show that there were a number of spikes that gave an indication of what could occur some 10-25 days down the line IF the cold occurred in the longitude of the UK.

I will now try and find the lrf stuff I used to do and see if in that I gave any indication of a cold spell.

It was certainly the case 2008-2009, just looked at, that it predicted quite well a cold snap.

It is something that amateur and professional alike are striving to get a deeper understanding of, to my mind it does open up a fresh way of trying to predict some time down the line when a cold spell is likely so it has to be an advance.

It would be nice if folk rather than showing those cases that did not work, for whatever reason, also showed cases where it did work. Let's try and be polite to one another folks, its only the weather at the end of the day and none of us has any responsibility (correct me anyone if I am wrong) with trying to ensure anyone against severe weather of whatever kind. That is apart from being a concerned and friendly neighrbour where needed.

[Barry12]

I know it's still too early, but what are the current signs that point to a colder than normal winter, and the signs that point to a milder than normal winter?

[johnholmes]

I HOPE this is the correct lrf I did in 2009 with a prediction for a colder spell, knowing me its probably the wrong year!

anyway I'll post it and then check if I have got the correct year

No 39 lrf issued 20Nov for 30 nov-10 dec.pdf