mcweather
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Put into the mix the usual poor modelling of arctic high pressure systems within the day 10 period, and add to that the further difficulty in trying to model the transfer of upper vorticity energy across the pole from Canada to Siberia, the usual advice of sitting back and trying not to over- disentangle the mischiefs of each and every intra day face value model operational output suite becomes ever more pertinent.
The pleasantly seasonal rather cold mid latitude high solution advertised in the shorter term looks to be well calculated by the models, but best be wary of reading too much into, and over anticipating, any lasting legacy (if it happens) from flattening out of the pattern to any long-lasting and meaningful extent thereafter with associated westerlies.
Whilst this is for sure a distinctly plausible (transitory) response to the energy transport across the pole, we should bear in mind that destination PV Siberia represents the next crucial step along the way with this winters pattern. This is said within the context of a very beaten up and weak polar vortex. It also represents a polar opposite to what happened last year in early December as Siberian energy transferred across to the Canadian sector as part of a centrally organising steroidal vortex that spat deep low after deep low across the atlantic towards us.....
Notwithstanding the uncertainties with regard to risks with over progressive model attempts to ditch the high to the east/north east in the short/medium term, the eventual outcome of energy balancing towards the Siberian sector will provide the fresh impetus anyway to the cold pooling SAI feedbacks which have been proven in recent weeks modelling to be in action.
We shouldn't fret too much over questioning timing when this next stage in the process is completed - even delayed by a short time. I stated in a previous post that this overall seasonal pattern process, once begun, was likely unstoppable and by the time the up-coming re-shuffling across the polar field has occurred, I would very much expect the next cycle of westward pattern backing to continue with vigour, whatever happens with regard to polar field modelling uncertainties in the shorter term.
The upping of the ante in the wave breaking battle as a consequence of this takes us ever closer towards the very back-end of the year and the increasing likelihood of an SSW. Its worth riding a short troposphere/stratosphere bombardment pause while the pattern re-sets
@blizzard 81 - will send a pm message
As ever Tamara, a sensible and balanced post looking at the much bigger picture. For sure it is that bigger picture that we have to look at to get us to some genuinely wintry weather. The ideas from yourself and Matt Hugo about late December for a possible pattern change to cold have for me always been the ones which were most likely. I thinks perhaps we have been spoilt by Dec2010 especially here in the south. ( It was the coldest December since at least 1879 in south and east Dorset!) into thinking that cold should arrive on the first of December. Never a likely scenario with our geographical position in the world.
Year and years of winter weather watching have taught me that patience is the key and now that we are getting to know so much more about how the strat, SAI etc have on shaping our winters it will be interesting to how the signs and signals playout and the global seasonal models unravel. The current holding patterns will have to be got through but come the middle of December I think some very interesting synoptics could start to show up.
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Winter Forecast update Sun 30th November 1PM.
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Look forward to it with great Interest Steve.
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very best of luck with the forecast BFTP. I'd take that anytime. I like the idea of 18/19th Feb for a Blizzard as it will be the 37th anniversary of the Great Blizzard of 78 in the southwest.
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Smiler when is this cold shot coming ? Even though things are looking a little more settled there is still a lot of low pressure to the NW which I think is where we don't want it !
Hi Kimb
A genuine cold shot is unlikely to arrive before December, there are plenty of things happening in the arctic with the polar vortex which suggest that cold will get to us but these things have a lag time between them happening up there and their consequences down the line for us.
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So we are almost halfway through November and still awaiting the first cold spell. For some this may come as a disappointing surprise but for others it is to be expected and par the course for a high SAI weak EN year.
The latest Anomaly charts are pointing at a good deal of Northpole height rises which is great news for this winter, but unfortunately for now we see the continuance of the Atlantic trough. Look at the NAEFS and ECM ensemble cumulative day 6-10 highlights this well.
NAEFS
00znaefsCumulative500mbHeightAnomalyNH240.gifECM
They are very similar indeed
There has been a lot of excitement about the forecast Strat warming, but I have not been excited as some as of yet. To recap we are seeing an upper based wave 1 warming followed by strong (for this time of year) wave 2 activity. The wave 1 displaces the upper polar vortex towards the Atlantic sector, and to some extent the lower vortex follows suit. However when the wave 2 hits it is critically hitting the Atlantic sector from Scandi and not Greenland. This has led to the split daughter vortices residing central Russia and western Greenland. This leaves the UK at the mercy of the Atlantic flow. I think that I mentioned earlier this month that unless we see a tropospheric led upwelling wave 2 break from the Greenland area then we would be unlikely to see significant cold this month and that still holds true.
I do not expect that the split will orientate any better before the vortex reforms, however, the vortex has taken one hell of a knock and it is still 'ripe' for further knocks this winter.
Another reason for the continued Atlantic presence can be found in the MJO forecasts.
http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/clivar_wh.shtml
The ECM and UKMO have both suggested forecasts to phase 2 - Well no surprise here in the forecast composite - err Scandi high and Atlantic trough noted there!
So, without giving too much away, I would be surprised if we were to see a significant block in the right position to lead to prolonged cold until at least Dec. However, ba is right when he suggests that we should want to keep the Scandi block - that is the precurser to possible later strat changes further into winter.
A great deal of common sense in Chionos post I think perhaps because the OPI did so well from a cold and snow lovers point coming in at its second lowest ever reading many thought this meant that we would see signs of deep cold almost immediately, this was never going to be the case.
The boxing analogy that Snowking has used in his posts is probably the best way of looking at what is happening to the vortex and even if does park over Greenland for a short while this doesn't mean that it is not continuing to take major hits, by the time we get into December the vortex will be pretty punch drunk and starting to fall to pieces it is then that we could realistically expect something that may bring cold and /or snow to our latitudes.
My advice is to hold tight be patient and pay particular attention to the posts from Chiono, Snowking, Recretos, Tamara, Blue army, Nick Sussex and of course Mr Murr because it is from these that we will be able to build the best picture of what is likely to happen and believe me it could be very good indeed.
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In light of Ian F posting last night that the meto see nothing cold from any output out to 15 days, it is always refreshing to see the one of the models they use turn round and bite them on the bum. lol
However we have seen the ECM do this at 240 before only for it to go up in smoke, if the same chart or one very like it comes within 7 days then we might be talking.
Having said that, the background signals are far more conducive to such a chart than they were last winter so the ECM may be on to something.
The strat thread is proving a seriously fascinating read with black holes now appearing on the anomaly charts over the arctic regions.
Good to see TEITS posting again too.
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No I want this set up - because of the implications in the heart of winter.
The other set up, the amber nectar, is the wave 2 trop led wave break into the strat from the Greenland plateau, but I would still rather wait for that until at least December, when the benefits will be greater.
I,m with you Chiono there is no point getting the' holy grail' now We just need to keep sseing the vortex under attack and weakening so that we can then decimate it with wave 2 trop led wave breaking during december that way we could get a really cold winter overall instead of just an early spell and not much else like 2010/11.
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Its all just a bit confusing for the less knowledgable like me. Ive been listening and learning a lot over the past few weeks, in particular Steve Murrs posts. For example, the last frame of ECM tonight looks to be sucking heights over to Greenland as he suspected would happen, as shown below:
But then weve had both Ian and snowballz on today, who both work for the Met Office I beleive basicaly saying nothing is showing up, and as we know, they have so much more data.
Can even they be caught out and perhaps have to make quick adjustments/changes to their outlooks very quickly?
Much though I have immense respect for the Met office and all the work they do, their forte is short to medium term forecasting which is what they are paid mostly to do. They will almost never say anything too exciting about cold and snow until it is nailed on within seven days.
Even back in Nov 2010 when this place was going nuts as the ensemble graphs showed temperatures falling off a cliff the Met office medium range forecasts were worded extremely cautiously in terms of ''possiibly turning colder later in the period with an increased chance of showers turning to snow in the north and east''
The experienced members on here could all see what was going to happen but the Met office with a national reputation to protect will always err on the side of caution especially with likes of the Daily express and James Madden willing to snipe at every opportunity.
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how many have been -2 or below? Can anyone post the years please?
2009 John.
An admittedly small sample field but a 100% correlation none the less. LOL
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At this point, I am really happy with the way the first half of November is shaping up, the analog match for November matches up really well with the forecast anomaly charts, with the exception of even better heights in the Arctic.
Even with average temperatures, one could expect periods of below average countered by above for the rest of those months. And December is certainly an intriguing month. The November strat conditions will tip the scales either way......
Hi Chiono, Am I right in thinking that the even better hieghts in the arctic you refer to make it more likely that December will be an intriguing month in a wintery sense.
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He might do if he was predicting ridiculous heat associated with an unforeseen doubling of solar heat and telling us we were going to have 100f in January!!!
No he tends to leave that sort of thing to Ian Brown
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IT WILL BE A MILD wINTER.........WITH TEMPS AROUND 13C-15c .....Less windy....and drier...........Early Spring .......should start second week of....February......................NUFF SAID.....
Crikey I didn't realise Ian Brown had a son called Troy.
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Our old friend Ian Brown, of the (completely busted) theory of winter modernity, has posted his thoughts for the winter on another forum http://www.ukweatherwatch.co.uk/viewtopic.php?f=98&t=4564&sid=bc6d1a9e42838471b70772eb494944c8 :
It's like he never left (2009 that is)
But seriously, fair play to him for putting a forecast out again, publishing an LRF takes guts and who knows, maybe he'll get it right this time (although for obvious reasons I hope not) Ah yes The Madden of Mild.
Does anyone else remember his Anglo saxon four letter word moment a few winters back when after telling us there was no way a cold scenario could develop (despite it being obvious to most of the rest of us that it would) the charts then went into cold and snow territory.
What deep joy that brought.
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I think some are missing Johns point here.
The point is, that a negative OPI does not necessarily lead to a cold winter in the UK.
It increases our chances as it correlates to a negative AO. That is the whole point of the OPI.
A negative AO (along with other factors) increases the chances of a colder winter for EUROPE of which we are a little island on the fringes.
Johns study is specific to the UK, not Europe as a whole
In short, it doesnt guarantee the coldest winter since the Ice Age but it does give us a fighting chance of being able to build a snowman this year! ⛄
Yes that's true but it does tend to lead to winters with substantial spells of cold/and or snowy weather, whether the winter is cold overall or not.
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Just on point 1 - absolutely true, but the positive point is that up until now all <-1 OPI years have featured below average Winter CET's.
So actually in the context of this winter and people searching for cold the CET relationship provides hope. You are absolutely correct, and who knows perhaps something such as that may occur this winter, but up until now the CET actually provides a good correlation to the OPI, which I'm sure is comforting to many
SK
Thanks Snowking and I do take your point and the CET-OPI relationship is a fascinating one.
I think what I wasrather clumsily trying to get across is that CET is not a great way of showing what the weather actually was, just what the average temps were and that can quite misleading in that in an average CET month the actual weather may have been anything but average.
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Just a couple of points.
Number 1
Why the obsession with CET in relationship to cold weather brought about in negative OPI winters?
One could have a mild first two weeks of January a cold and snowy second two weeks which continued into the first two weeks of feb before a mild second two weeks in feb. You would have had a very significant spell of wintery weather. which would tie in with the negative OPI suggestion of colder weather regimes. Yet official CET records used by Metetorologists would register two average months whereas the rest of us would be talking about the amazing month long cold and snowy spell . In other words the real weather as opposed to the statistics
Number 2
The way I view a Negative OPI below -1.5 is that it equates to an atmosphere more predisposed to allow cold set ups to affect the UK.
So this time round with a sub -2 OPI , although in the UK ,cold weather is never 'in the bag' until it's 'in the bag'. This year we have a bag that is being held open and the right way up whereas last year we didn't even have a bag.
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A really well reasoned piece of work Steve. I look forward to your final winter forecast later in November.
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Here's a thing.
We all know that even in mild winters the usual suspects can still get snow often due to being close to windwards coasts or altitude.
But what about a relatively snow free location like mine in Central south Dorset?
Looking back through the OPI table for the last 36 years every one of the years with a reading of minus 1 or below has produced a spell/spells of heavy snow and/or intense cold.
Sometimes we didn't even need to get as low as minus 1. The great Blizzard of Feb 1978 in southwest England came on the back of and OPI of-0.95 for October 1977 and even a reading of -0.85 in October 2010 was followed by the coldest December on record in much of Dorset.
So I for one am certainly looking forward as we home in on a sub minus 2 OPI. It will be a good test.
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As you well know, we've had all those factors many times before, how many times have you seen snow in the last twenty years? Would you be telling all your locals that we're in for a cold Winter because of a negative number?
To be fair Mapantz I cross referenced all the years with a with an OPI number greater ( more negative than minus one) and found a very good correlation
for worthwhile snowfall in Dorset,
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Yes cloud ten and the the weds12z cfs 9 month run reflects that with some cracking daily charts from the 8th Dec onwards, would be looking at a christmas snowfest if that lot came off. here's hoping.
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I work outdoors but I would take three months of frost and snow over three months like last winter anytime.
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Parts of Dorchester have been hit bad, lots of calls to the fire brigade apparently.
Quite a lot of lightning and heavy rain here at Broadmayne in the past hour Mapantz
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Oh great noble Winter 2014/15, it would be an absolute pleasure if you brought this to the UK this year. An Easterly of such elegance, it would dazzle the cold and snow fans' hearts with joy and happiness. It is an honour.
Oh yes please I remember it well, trrudging past moonlit 6 foot snowdrifts in the Purbeck hills. Fabulous.
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You'd like to think so but not here. We've had the odd couple of inches, but it melts the same day.
2009 was the first time in over ten years that an inch of snow settled. January 2010 - I was in one of the very few places that didn't have snow settle. December 2010 was OK, but again, about 3 inches fell- it melted a few hours after it stopped snowing. Nothing in 2011/12, a little bit in 2013. Pathetic compared to the late 70's & early 80's
Ah yes I remember it well Mapantz 6th January 2010 the day of the Great red level ( its definitely coming you must take action kind) Met office warning of 12-18 inches of snow for Dorset . Schools closed early people were sent home from work. not a single flake fell possibly one of the greatest Met office fails on record.
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But seriously, fair play to him for putting a forecast out again, publishing an LRF takes guts and who knows, maybe he'll get it right this time (although for obvious reasons I hope not) 
Model Output Discussion 1200 hrs 15/11/14
in Forecast Model Discussion
Posted
Nice one Bobby dog a clear antidote to all the worrying about the PV possibly getting established over Greenland.