Winter 2013-2014 Discussion- Part 2

[sebastiaan1973]

Anybody a clue what the record is for the highest AO in december? And for the periode november-december? Thanks! AO november 2013 was 2nd highest!

[hillbilly]

man this winters reminding me a lot of w2011-2012 again a mild october folowed by a crap winter. The saving grace of that winter was feb 2012 with that cold spell and even then it was nothing to sing about here. No matter how peeps dres it up the charts r crap for us coldies. The patern we r in atm can hang around for ages and it's a caravan to get out of. Don't get me wrong guys i'm not by any mean saying winters over b

So much for all those bigging up this winter...they know as much as the guy in cardboard city with a bottle of whisky....and me.Then again winter ends in april in these parts!

[keithlucky]

Matt Taylor reveals whats the chances of a white xmas http://t.co/MgtpkpF2gH

[matty40s]

Wow, and they carried on playing and in short sleeves! We are lucky if we see 8 inches in an entire winter - what I'd give to see a blizzard like that right now, or at some point this winter :-)

 

galatasaray v juventus match abandoned....

[irishlad69]

we still have two weeks until Christmas day, I aint giving up yet

[BornFromTheVoid]

Anybody a clue what the record is for the highest AO in december? And for the periode november-december? Thanks! AO november 2013 was 2nd highest!

 

2006 had the most +ve AO for December, at +2.282, just ahead of 2011 at 2.221

 

 

2011 also had the strongest +ve AO for November and December combined (which surprised me a bit). December this year would have to be near +1.7 to beat 2011.

It's averaged close to +1 say far this month I'd say, but with the forecast going for some very +ve values, I certainly wouldn't bet against beating 2011.

 

 

[Peter H]

i have this horrible feeling that this winter is going to be one of the mildest winters we have had for a few years, no science to my opinion, just a hunch, fingers crossed im wrong, lol. but should it be the case then i hope i see some snow in Feb when im in Rekjavik.

 

Yes, same here.

 

Extremely mild this evening, and I actually saw someone walking down the street in shorts.

 

T shirt weather ! 

[Peter H]

man this winters reminding me a lot of w2011-2012 again a mild october folowed by a crap winter. The saving grace of that winter was feb 2012 with that cold spell and even then it was nothing to sing about here. No matter how peeps dres it up the charts r crap for us coldies. The patern we r in atm can hang around for ages and it's a caravan to get out of. Don't get me wrong guys i'm not by any mean saying winters over b

Your dead right, and we didn't even get that cold spell in Feb 2012.  

 

I have a feeling we're getting into another rut of really mild snowless winters again. 

[sebastiaan1973]

Thanks BftV. So interesting times ahead. The extreme values (positive and negative) of the AO are remarkable!

[Weather Boy]

Your dead right, and we didn't even get that cold spell in Feb 2012.  

 

I have a feeling we're getting into another rut of really mild snowless winters again. 

 

Ha ha, so we've gone from writing off a whole winter 10 days in to writing off a whole clutch of winters based on some unpromising model output!

 

Who knows, you could be right, but I think I'd want something a bit more scientific than that to back you!

 

At the risk of being a little off topic, is there any evidence in support of the notion that seasons go in phases e.g run of wet or at least no better than average summers 2007-2012, the very mild winters in the early 2000's, and warm sunny summers 1989-1991?  Impressionistically, it seems that way, but has this ever been studied, and if does exist, what causes it?

[jvenge]

Ha ha, so we've gone from writing off a whole winter 10 days in to writing off a whole clutch of winters based on some unpromising model output!

 

Who knows, you could be right, but I think I'd want something a bit more scientific than that to back you!

 

At the risk of being a little off topic, is there any evidence in support of the notion that seasons go in phases e.g run of wet or at least no better than average summers 2007-2012, the very mild winters in the early 2000's, and warm sunny summers 1989-1991?  Impressionistically, it seems that way, but has this ever been studied, and if does exist, what causes it?

No, there isn't. Of course, you have the El Nino and La Nina years, which I think is every 3-5 years (from memory) and that can impact the weather, but other than that, there are no short term cycles I can think of which would impact just a few years. Some people link to 30 year or so cycles, but even in those you can get those few odd years! Have a google for El Nino and La Nina effects.

 

Tis a bit soon to be writing winter off so soon in. I mean, December is an early winter month. Look what happened in Jan, Feb and March this year.

[Snowynorth]

Cant get my head round the fact that the cfs keeps trying to push a high pressure over Scandinavia. I know people say cfs is inconsistent blah blah  but it has regularly pointed to high around this region for x mas week. This model must have picked something up or else why would it show these runs!!!!

 

http://modeles.meteociel.fr/modeles/cfs/runs/2013121006/run1m2/cfs-0-348.png?06

http://modeles.meteociel.fr/modeles/cfs/runs/2013121100/run1m/cfs-0-366.png?00

Edited December 11, 2013 by iamstuart

[Dr Forinor]

Cant get my head round the fact that the cfs keeps trying to push a high pressure over Scandinavia. I know people say cfs is inconsistent blah blah  but it has regularly pointed to high around this region for x mas week. This model must have picked something up or else why would it show these runs!!!!

 

http://modeles.meteociel.fr/modeles/cfs/runs/2013121006/run1m2/cfs-0-348.png?06

http://modeles.meteociel.fr/modeles/cfs/runs/2013121100/run1m/cfs-0-366.png?00

I'd be interested to hear other people's opinions on this.

[Snowynorth]

I'd be interested to hear other people's opinions on this.

Yes thats why I posted it. Just can't understand why it's run that outcome too many times

[Nick B]

I have to say, I now view the CFS outputs with a degree or two of scepticism.  Although I agree that single runs are worthless and it's better to interpret trends over a long period, when those runs show these blocking highs for many weeks ahead on successive occasions e.g. for late November and then nothing happens, then they do so again for early December and guess what? - nothing, then again for later December (you get the picture), I begin to question whether there is a bias towards those scenarios in the current scripting.

Certain LRF's which don't scream cold for the first part of winter seem at the moment to be doing alright.

[Cheshire Freeze]

I'd be interested to hear other people's opinions on this.

 

For a couple of months now I've been trailing the mixed December, cold thereafter scenario (as per winter forecast). We've had the brief northerly to start the month, a spell of benign, HP dominated weather and what looks like an upcoming unsettled spell. A Pattern change (to cold) just after Christmas and into the New Year period would fit in very well with my personal long range thoughts.

[Dr Forinor]

For a couple of months now I've been trailing the mixed December, cold thereafter scenario (as per winter forecast). We've had the brief northerly to start the month, a spell of benign, HP dominated weather and what looks like an upcoming unsettled spell. A Pattern change (to cold) just after Christmas and into the New Year period would fit in very well with my personal long range thoughts.

Can you go into more detail in regards to this cold pattern change? 

[Cheshire Freeze]

Can you go into more detail in regards to this cold pattern change? 

 

'Winter 2013-2014 looking to feature a predominantly -AO and a fairly notable -NAO anomaly across winter as a whole. December looking to be the mildest of the three months with a mean temperature not deviating far from average. January and February to feature periods of severe cold which will likely see winter 2013-2014 significantly colder than average on balance'

 

That was from the 23rd November. December was always likely to be the mildest of the 3 months DJF if my forecast is anywhere near accurate. A fairly significant pattern change to see January much colder than average so therefore a pattern change around the New Year period would fit in well with this proposed shift in synoptics.

 

There's nothing to be specific over at present other than pressure should be higher than average to our N in general. I'm certainly not discounting a '78/'79 type of scenario at present. Given the extensive cold pooling which is locked to our N at the moment, any wedge of heights to our N could have potentially explosive results in terms of snowfall for the UK.

 

Here is an example of a fairly typical synoptic set up we'll see during January...(if all goes well)

 

Edited December 11, 2013 by CreweCold

[feb1991blizzard]

'Winter 2013-2014 looking to feature a predominantly -AO and a fairly notable -NAO anomaly across winter as a whole. December looking to be the mildest of the three months with a mean temperature not deviating far from average. January and February to feature periods of severe cold which will likely see winter 2013-2014 significantly colder than average on balance'

 

That was from the 23rd November. December was always likely to be the mildest of the 3 months DJF if my forecast is anywhere near accurate. A fairly significant pattern change to see January much colder than average so therefore a pattern change around the New Year period would fit in well with this proposed shift in synoptics.

 

There's nothing to be specific over at present other than pressure should be higher than average to our N in general. I'm certainly not discounting a '78/'79 type of scenario at present. Given the extensive cold pooling which is locked to our N at the moment, any wedge of heights to our N could have potentially explosive results in terms of snowfall for the UK.

 

I can see enough disruption to the vortex through wave activity to give us some colder shots towards mid jan but looking like late Jan for any chance of persistent HLB or February IMO.

[Cheshire Freeze]

I can see enough disruption to the vortex through wave activity to give us some colder shots towards mid jan but looking like late Jan for any chance of persistent HLB or February IMO.

 

We don't really need a blockbuster HLB of 1060mb to ensure cold and snowy conditions though. Just enough disruption to allow discrete pressure rises around the Iceland-Svalbard area will probably suffice. This should act as a trigger for lowering heights across mainland Europe and a backed flow across the UK in conjunction with cold pool approaching from the E.

 

We already see this at the end of FI on the GFS 12z with pressure lifting around the Iceland area around the top of UK LP. It's this situation which eventually leads to LP being shunted towards mainland Europe with an E'ly flow on the N'ern flank and negatively tilted LP following in the Atlantic which serves to lock the pattern in.

Edited December 11, 2013 by CreweCold

[feb1991blizzard]

We don't really need a blockbuster HLB of 1060mb to ensure cold and snowy conditions though. Just enough disruption to allow discrete pressure rises around the Iceland-Svalbard area will probably suffice. This should act as a trigger for lowering heights across mainland Europe and a backed flow across the UK in conjunction with cold pool approaching from the E.

 

Of course its possible and you don't always need a big pressure rise to the North to take advantage of sliders but most on here crave spells that don't just get the snow washed away a couple of days later, I would rather have a big persistent block to be on the safe side but if I got a 2 foot dumping I don't really care whether the trigger would just be a thin slither 550 heights or a 1060 surface & 500mb high right the way from GL to scandi or even cold zonality but I always think the chances of a memorable spell increase when the signal for massive PV  disruption and HLB exists.

[Cheshire Freeze]

Of course its possible and you don't always need a big pressure rise to the North to take advantage of sliders but most on here crave spells that don't just get the snow washed away a couple of days later, I would rather have a big persistent block to be on the safe side but if I got a 2 foot dumping I don't really care whether the trigger would just be a thin slither 550 heights or a 1060 surface & 500mb high right the way from GL to scandi or even cold zonality but I always think the chances of a memorable spell increase when the signal for massive PV  disruption and HLB exists.

 

Haha well my best snowfall in 10+ years occurred last year with a little slither of heights. Having not received more than 5cm throughout '09/'10 and '10/'11, a big fat Greenland high promises nothing here.

[Summer Sun]

deleted

Edited December 11, 2013 by Summer Sun

[Weather-history]

I'd be interested to hear other people's opinions on this.

Garbage in, garbage out.

[BornFromTheVoid]

I'll give an update on the CFS blocking trends tomorrow, but so far, it's looking like it got December completely wrong.

 

Anyway, I thought I'd have a look at some late December mild to cold CET switch arounds from recent years.

 

Year: 1st to 20th: 21st to 30th: Difference

2000:      7.9C               2.0C            5.9C

1992:      5.5C               0.0C            5.5C

1985:      8.2C               2.8C            5.4C

1979:      7.7C               2.5C            5.2C

 

Some historical examples

 

1772:      7.0C              0.7C             6.3C

1820:      6.8C              1.0C             5.8C

1831:      7.8C              2.1C             5.8C