Jump to content
Thunder?
Local
Radar
Pollen
IGNORED

Winter 05/06 Summary-


SMU

Recommended Posts

Posted
  • Location: New Ash green 150M / 500 FT
  • Location: New Ash green 150M / 500 FT

    Good Morning-

    Im aware that there is a seperate thread running concurrent- so If admin feel this clogs the forum up to much then feel free to move it-

    There is however a lot of different things covered-

    Firstly- As we have seen out the last 'meteorlogical' days of Winter Ive tried to put together some information on what this Winter has delivered- but more importantly where I think it stands in terms of things moving through the next few years-

    We have seen the Phrase 'even larger teapot' used frequently over the past Season- and whilst Im sure that it did have a definitive meaning a few years ago I think now we are actually moving away from the Post 88 era which was dominated by the evervesent Westerly flow-

    The assumption here was that the UK could not sustain any form of cold spell due to the persistence of the Icelandic Low & Azores high- & there is definate data to support that..

    Although Winter 04/05 could now POSSIBLY be defined as the POST even larger teapot-

    Anyway...

    This was my first Season preparing a Winter forecast,Ive provided the link should people still wish to browse

    http://www.net-weather.co.uk/forum/index.p...opic=26623&st=0

    To a degree though Im very pleased of the outcomes in terms of

    1) Precipitation - being on the Lower than seasonal average

    2) Cyclonic Behaviour- Being in a convoluted state ( Higher frequency of blocking)

    3) Overall Temperature- I wasnt quite right there- as it has turned out on the average mark- but below for england & wales-

    Next year I intend to produce another Winter forecast However there will be NO attempt to pin down Monthly CET- it will be based on the 3 Primary factors above at a Seasonal Level- I doubt there is the skill from anyone to drill forecasts down to the week despite having a wealth of information at our finger tips-

    The discussion as we entered the latter part of November- and often throughout the year was for evidence of so called 'pattern change'across NW europe- This was away from the westerly norm towards a more blocked scenario-

    What we couldnt pinpoint was the route cause if any could be attributed for driving a change in Synoptics- Indeed was it just a mirage- or could it be attributed to-

    The NAO Cyclical Shift??

    Global Warmings influence??

    Reduced Sunspot Activity??

    SST Patterns??

    Other??

    Speculation has been endless-

    Although now With the Heinsite we can begin to say with further tentative evidence that we are moving away from the atlantic dominated Winters of the past 17 years-

    However a cautionary note- We have a dataset of evidence that covers only 2 years of possible 'change'- This means even with the magnitude of evidence that could be provided in favour of the new 'norm' it may still be a rogue or anomaly in the otherwise relentless warm up-

    Personally I think that it is an amalgamation of all the Teleconnection patterns ( & a few others ) that are beginning to conspire against the omni-present Icelandic Low & azores/Bartlett Highs-

    A few things immeadiatly strike me off the 'bat'

    Ask yourself these questions-

    How many Azores &/or Bartletts have lasted longer than a week since Mid November??- You would be hard pushed to find any....

    How many Warm inversions have we seen this Winter??- Zero

    How many Cold Inversions have we seen this Winter-?? 2 significant ones- ( some may argue that a cold inversion isnt important- however I disagree as you need a cold high in place to deliver that cold inversion- & indeed the second one brough Snowfall in 850 temperatures of some +5 degrees 850 HPA)

    What about recorded Maxima this Winter- Some stations reporting NOT seeing a surface temp of above 10C for the WHOLE winter- Refer to Dave J's post for this info-

    We can also attribute the Colder CET's to lower night time minima- The higher incidence of Frost in all regions has been noticable- with I think the lowest recorded minima this last week of -19C ( un-official from Weather online)

    Those were just some of the things that spring to mind without much thought-

    The Key though is to see whats driving this-??

    At the top of my list this Winter I would certainly put the Stratospheric air temps- especially at the pole as the big single factor of redundancy of the Westerlies-

    The basic assumption ( which is well documented) has the COLDER the Stratospheric gas the 'faster' the Artic & polar jet will flow due to the Stronger polar vortex-

    The winters of the 90's has some of the Coldest Stratospheric temps bringing in some of the Mildest CET returns-

    Ive attached a segment of work done on this Correclation between Warmer Stratospheric temps & Higher Pressure blocking- ( Compliments Typhoon tip NE US WX)

    post-1235-1141790671.jpg

    post-1235-1141790700_thumb.jpg

    Noticably the S.GAS has been remarkably warmer this year, this has been reflected well at higher lattitudes by the weakened vortex & higher heights observed at the poles-

    The Easiest way of having a snapshot of the height situation over the pole is to observe the AO ( Artic oscillation)-

    Strongly Positive correlates to A fast flow & strong vortex- a Negative AO is the inverse of that.

    As we can see from the Attachment the 'negativity' of the AO has been very Negative this Winter

    post-1235-1141790732.gif

    - So much so that since recording of the AO began in 1950, December had the Third most 'negative' reading-

    http://www.cpc.ncep.noaa.gov/products/prec...ent.ascii.table

    This however DOESNT Correlate to blocking to the North of the UK- its more a reflection on the global Mean Pressure patterns and shows how convoluted the Jet stream is-

    Again the correlation there is - Strong -AO = Convoluted Jet stream-

    We can continue the Stratospheric Gas temps through out this year with the zonal Mean temps at 50Mb at various Lattitudes- Already at the start of 2006 we can see the Warmer start to the year from a lattitude 65N- up to 75N-

    post-1235-1141790806_thumb.png

    Now look at how cold 1990 was at the same time-

    post-1235-1141790851.gif

    As we can see there is some 25 degree difference between 1990 & 2006 between 60 & 75N-

    There is an approximate 25 day propergation wave delay in the Stratospheric gas temp change & the observed change in Surface Patterns-

    You would expect that the AO>NAO Link would come into the equation here- but the NAO has been ( And always will be) the wild card here-

    There is a linear correlation with the negative AO Phase of about 0.6 to a Negative NAO phase- ( 1 being a total correlation & -1 having no effect what so ever) - Sadly for this Winter the Mean AO pressure anomaly delivering the 'negative' goods has been in situ over the Pacific or the far east- meaning that for this Winter the 0.4 part of the correlation has been demonstrated.

    That Said whilst the NAO hasnt been in full negative Phase it hasnt been a total washout of a Winter- Far

    from it-

    As we can see the NAO signal has been rather muted- probably because of the significant phase of the Pacific jet- However what we do see is although the Negative trend is not exactly amplified nor is the positive phases-

    Infact looking at the attachment below-

    post-1235-1141790884.gif

    We can see that there has been only one real positive phase at the start of Jan which didnt last longer than 2 weeks-

    Also we can see very cold air over the UK when the NAO is Neutral- This is perfectly illustrated by the 28 Dec 2005-

    We have a Neutral NAO with this Synoptic Pattern-

    http://www.wetterzentrale.de/archive/ra/20...00120051228.gif

    One of the highlights for me this winter has been the lower than Normal heights over the Iberian regions-

    This has gone some way to compensate the below Normal heights over greenland- What it also does is teleconnect to having a ridge supporting between the 2 anomalies- and this has allowed on 3 occasions a tongue or loop of Cold air to run back through scandi & filter in the back door of the UK-

    Sadly ALL these occasions have been at a point whereby that process had advected warmer air into central Europe ahead of the blocking- So we have a process of Cold replacing Milder blocking-

    There has however been a couple of occasions whereby we *ALMOST* got into the situation of Very cold air flowing from Very cold blocking- This came from when the polar vortex became displaced on the Southern side of the Russian high in January- this again stems from a Largly Negative AO set up-

    it is my Suggestion that again this pattern will cont

    Remember this going forward-

    NEUTRAL NAO still can equate to cold UK temps-

    The reason I highlight this is with the Pacific drivers the PDO & QBO being in phases that could lock in over the coming Winters we will have have to look forwards to more neutral dominated periods of the NAO despite the SST signature possibly become the key tripole Predisposing the NAO towards negative-

    With this in mind assuming that next year we arrive at a similar teleconnection juncture-

    Ie the PDO & QBO exhibiting the Strong Pacific Jet trend then most certainly we can look forwards to more of the SAME trend-

    This will tend to be in the START of the winter for Zonal or Semi Zonal flows punctuated by flat shaped mid lattitude blocking highs with Strong Negative height anomalies either Side -

    The Mean pressure anomalies for Dec & Jan from Philip Edens Site show exactly what I mean-

    http://www.climate-uk.com/monpre/0512.htm Dec 2005

    http://www.climate-uk.com/monpre/0601.htm Jan 2005

    Then as we reach the latter stages of the Winter this is where the Negative NAO signature can possibly take over (overwhelming weakening phases of the PDO & QBO )- allowing Larger Circular shaped highs developing indicating a meridional or Highly Meridional flows to develop

    Look at Feb 2006

    http://www.climate-uk.com/monpre/0602.htm

    We can see the Nice High lattitude blocking from perfect Spawning conditions of Weakened Pacific Jet & Warm Stratospheric gas- between 60 & 75N

    Over the next few years this could also POSSIBLY encompass the first Parts of March- ( which is rare these days-)

    http://www.climate-uk.com/monpre/0503.htm

    March 2005 started the trend- but the pattern collapsed early on-

    Using Philip Edens data brings me onto a topic discussed by many posters throughout the winter from forum to forum-

    The inference that the mean location of the polar front in Winter has migrated further north -

    Philip has furnished me with some data that goes a way to prove that yes this is the case-

    Illustrated below

    post-1235-1141793333_thumb.png

    post-1235-1141793473_thumb.png

    post-1235-1141793544_thumb.png

    post-1235-1141793600_thumb.png

    As we can see both the Mean Low pressure & High pressure locations have made gradual progression Northwards- with further pressure INCREASES in the Iberian regions over the last 10 years-

    As well as lower centre pressure observed is lower towards iceland-

    This in my opinion does correlate VERY well with the increased frequency of Bartlett highs observed as well as that 'omni-Present' Icelandic Low-

    Now take this febs Actual-

    http://www.climate-uk.com/monpre/0602.htm

    Notice how the Icelandic Low has eased off a long way further west- Also the Azores High & Bartlett pressure belt is weaker and slightly further South-

    Notice the UK is almost in the 'Col'- with Pressure significantly higher than the norm to the NE-

    It looks more like a chart from the 61-70 mean....

    Another pointer going back to prove that this Winter is 'Impressive'..........

    I suppose that does cover most things this Winter- remembering that this is in my opionion still a Transitional year- inferring that the following years 'should' trend further towards what we are seeing now-( the highest expectancy of a moderate to severe winter comes on 07/08)

    This would be a Strong fast Flat pattern to start, Amplified Slow pattern to finish- the key is at the start- I stress that should the Stratopheric gas warming continue at those Northern Lattitudes it will only be a matter of time we get a 'Proper' old fashioned Easterly Phase-

    These tools and many others will come 'out of the box' for the next Winter forecast- But for now is Asta la vista to the 'QBO et al'-

    Suffice to say though that anyone harbouring thoughts of breaking out that new George foreman Barbeque set may have to keep them on ice for a while yet-

    The feedback patterns at the moment, depth of the azores high & the warmth of the Stratospheric gas at 75N do not support an early season plume up from the South-

    As the models begin to see the gradients rapidly changing & increasing from the South in the medium term they will jump on any chance to drive that polar front back north introducing Warm air -

    Sadly as the ensembles have shown over the last week- Overwelming support for big Mild 850 runs doesnt actually arrive- and we are now looking at possibly a Snowy episode for Saturday 11th March-

    The ensembles at the moment reflect the prospect of the first warmth arriving after that- Dont count on it TO much just yet- It MAY happen although as the varifiaction stats are in the low 80'%s at day 5-(T120) & the feedbacks are POSITIVE towards more northerly blocking march may still herald some surprises yet.....

    Regards

    Steve :(

    Thanks again goes to Philip Eden for the Pressure data...

    Link to comment
    Share on other sites

    • Replies 25
    • Created
    • Last Reply
    Posted
  • Location: South Derbyshire nr. Burton on Trent, Midlands, UK: alt 262 feet
  • Weather Preferences: Extreme winter cold,heavy bowing snow,freezing fog.Summer 2012
  • Location: South Derbyshire nr. Burton on Trent, Midlands, UK: alt 262 feet

    Thanks Steve, a great read which explains very well our subtly changing winter.

    Many in here have followed this winter with great interest, watching out for clues as to where our next few winters might head, as you say last winter looked like the transition from the westerly dominated winters of the late 80’s and 90’s and this winter has definitely followed on from that.

    I think a few of us were disappointed during January when we got so close to hitting the Jack pot, regarding a very cold easterly, but thinking about this, it would have been lucky indeed to experience a very severe cold spell, this being the first such post ‘even larger teapot’.

    I agree and IMO we have much to look forward to, next winter 2006/7, may be another close shave, like this winter, but if this trend continues, sooner or later we will hit the Jack pot. :(

    Paul

    Link to comment
    Share on other sites

    Posted
  • Location: frogmore south devon
  • Location: frogmore south devon

    nice post steve will read it again when i get back from work later there's a lot to digest

    Link to comment
    Share on other sites

    Posted
  • Location: Dublin, ireland
  • Weather Preferences: Snow , thunderstorms and wind
  • Location: Dublin, ireland

    A great read Steve,

    I can only concur with all that you say.

    You have put technical detail to what I believe was a very special winter.

    More Frosts

    Virtually no Atlantic activity. I enjoyed the light winds.

    More easterly influence. I really did think we narrowly mised out on that cold blast from the east.

    Little talk of "topplers" or indeed any topplers.

    It is interesting though how many people here thought this winter was disappointing. I based my enjoyment on what I believe is a continuation of the synoptic change and what "could have been" and the hope that the good form will increase over the next couple of winters.

    Roll on next winter

    Link to comment
    Share on other sites

    Posted
  • Location: Shrewsbury,Shropshire
  • Location: Shrewsbury,Shropshire
    A great read Steve,

    I can only concur with all that you say.

    You have put technical detail to what I believe was a very special winter.

    More Frosts

    Virtually no Atlantic activity. I enjoyed the light winds.

    More easterly influence. I really did think we narrowly mised out on that cold blast from the east.

    Little talk of "topplers" or indeed any topplers.

    It is interesting though how many people here thought this winter was disappointing. I based my enjoyment on what I believe is a continuation of the synoptic change and what "could have been" and the hope that the good form will increase over the next couple of winters.

    Roll on next winter

    This winter has been far from disappointing-it's made me look forward to this coming winter even more than last years did!! A change is happening i think and others on here have noticed the same.

    Link to comment
    Share on other sites

    Posted
  • Location: Horley, near Gatwick
  • Location: Horley, near Gatwick
    A great read Steve,

    You have put technical detail to what I believe was a very special winter.

    More Frosts

    Virtually no Atlantic activity. I enjoyed the light winds.

    More easterly influence. I really did think we narrowly mised out on that cold blast from the east.

    It is interesting though how many people here thought this winter was disappointing. I based my enjoyment on what I believe is a continuation of the synoptic change and what "could have been"

    John,

    For me it has been disappointing because there's been very little 'weather'. November was great, with its frosts and fog, really seasonal and very nostalgic in its own way. But December, Jan and Feb have been hugely disappointing; but then I don't find merely seasonal temps or slightly below average temps inspiring, especially when they are combined with very dry, cloudy conditions. Very dull stuff. At least in a mobile pattern there is a chance of some weather! And likewise, you talk of easterly 'influence' but to my mind, the east hasn't influenced our weather a great deal unless you're speaking of persistent blocking in just the wrong place that killed off much of our 'weather'. 'Narrowly missing out on that cold blast from the east' is just it - that's pretty much a default postion for the UK - and indicative of an unfavourable jet. Whether the cold is only 300 miles away is neither here or there in my book; it's a chicken or egg scenario where the evolution of the jet produces precisely the cold pool that we can't quite tap in to!

    I appreciate our locations are very different but this is the first Nov-Feb period that I can EVER remember (and I'm 34) where, in my location, I have not had the opportunity to leave one single footprint in the snow. :(

    Link to comment
    Share on other sites

    Posted
  • Location: Dublin, ireland
  • Weather Preferences: Snow , thunderstorms and wind
  • Location: Dublin, ireland
    John,

    For me it has been disappointing because there's been very little 'weather'. November was great, with its frosts and fog, really seasonal and very nostalgic in its own way. But December, Jan and Feb have been hugely disappointing; but then I don't find merely seasonal temps or slightly below average temps inspiring, especially when they are combined with very dry, cloudy conditions. Very dull stuff. At least in a mobile pattern there is a chance of some weather! And likewise, you talk of easterly 'influence' but to my mind, the east hasn't influenced our weather a great deal unless you're speaking of persistent blocking in just the wrong place that killed off much of our 'weather'. 'Narrowly missing out on that cold blast from the east' is just it - that's pretty much a default postion for the UK - and indicative of an unfavourable jet. Whether the cold is only 300 miles away is neither here or there in my book; it's a chicken or egg scenario where the evolution of the jet produces precisely the cold pool that we can't quite tap in to!

    I appreciate our locations are very different but this is the first Nov-Feb period that I can EVER remember (and I'm 34) where, in my location, I have not had the opportunity to leave one single footprint in the snow. :(

    Hi PED,

    I can see where you are coming from.

    I suppose because I live in Ireland and we get more atlantic influence than you I have noticed the change in the less zonal activity more than a lot of people in the UK.

    Perhaps because I am a little older (49) and I have experienced all kinds of weather I now enjoy the synoptic studies perhaps more than the weather itself but I did love the frosts we had this winter

    Link to comment
    Share on other sites

    Posted
  • Location: Horley, near Gatwick
  • Location: Horley, near Gatwick
    Hi PED,

    I can see where you are coming from.

    I suppose because I live in Ireland and we get more atlantic influence than you I have noticed the change in the less zonal activity more than a lot of people in the UK.

    Perhaps because I am a little older (49) and I have experienced all kinds of weather I now enjoy the synoptic studies perhaps more than the weather itself but I did love the frosts we had this winter

    49? Wouldn't say I'm that far behind you fella! :( In fact, I feel about that this morning! As we said, our respective locations would produce a very different 'take'. The London area isn't great for much weather at any time of the year (unless it's unbridled summer heat you're after) so by that yardstick, it's been a remarkably bland winter. I do agree about the synoptics this year though, but no sooner do we get them then we get a rampant pacific jet that has scuppered any real enduring cold at almost every juncture. I just hope that the future is not a chilly, dry one.

    Link to comment
    Share on other sites

    Posted
  • Location: Coalpit Heath, South Gloucestershire
  • Location: Coalpit Heath, South Gloucestershire

    Mr Murr.....an interesting read! Perhaps people will now begin to accept/see that Winters are changing. My own feelings are that the first hints of change were in the Winter of 03/04. I have put this forward here many times but usually get pooh-poohed, with the exception of a hardy few like-minded souls (shalln't mention names!). I can only go by what I have observed though and cannot produce any other "proof" of a change. It is good to read what you have written. :)

    I suppose because I live in Ireland and we get more atlantic influence than you I have noticed the change in the less zonal activity more than a lot of people in the UK.

    Perhaps because I am a little older (49) and I have experienced all kinds of weather

    Good Morning, young John!

    Agree wholeheartedly with your comments regarding Atlantic influence, being a West coasterner myself.

    I too have experienced much weather, having turned 50 last month! :(

    Looking at the MetO experimental forecast for the Summer, the Atlantic is going to carry on losing it's influence. It will still be over you, but won't be making it to the mainland. :(

    Let's hope it continues it's westward retreat over the next few years!

    Link to comment
    Share on other sites

    Posted
  • Location: New Ash green 150M / 500 FT
  • Location: New Ash green 150M / 500 FT
    Mr Murr.....an interesting read! Perhaps people will now begin to accept/see that Winters are changing. My own feelings are that the first hints of change were in the Winter of 03/04. I have put this forward here many times but usually get pooh-poohed, with the exception of a hardy few like-minded souls (shalln't mention names!). I can only go by what I have observed though and cannot produce any other "proof" of a change. It is good to read what you have written. :(

    Morning All-

    thanks for th replies so far-

    Noggin- we may well have started a change prior to my dates-

    Feb 04 looks very much 'in sink' with the last 2 Febuary's

    http://www.climate-uk.com/monpre/0402.htm

    S

    Link to comment
    Share on other sites

    Posted
  • Location: Horley, near Gatwick
  • Location: Horley, near Gatwick
    I think what John may be referring to, and the essence of this discussion really, is that we may be seeing a transistional process back to more continental style conditions with easterly influences increasing over the next few winters

    Or, to put it another way, with westerly dominance seemingly on a retreat then the potential for easterly influence may well be on the increase, with the result that UK influence increases.

    Tamara

    Yes, the lack of zonality is the real nub of this argument, I'd concur with that, though it's a long track to equate a lack of zonality with a growing easterly influence (the Siberian high is, after all, a quasi-permanent feature of the winter much like the Azores). It's quite feasible that we in the UK could become stuck in the middle of such a pattern; pretty blocked and dry and sandwiched between a very cold and snowy continent and a mobile pattern across the pond. I'm more minded to keep my futuristic eye on the polar jet and the effect of the diminishing ice sheet at the pole. The further north that thermal gradient gets, the less likely we are to get poleside of the polar front. I'm no technical meteorologist but that strikes me as common sense. And yet again, SP, you're alluding to 'ifs' and 'buts'. Given the synoptic patterns over much of this winter, are you not amazed that I've not seen one single day of lying snow? Really, just what will it take?

    Link to comment
    Share on other sites

    Posted
  • Location: Ponteland
  • Location: Ponteland

    Steve,thanks very much for your review and the way thinks might develop in the years to come. For me the only disappointment has been the lack of snow in the North-East but the lack of winds and mild weather really made up for it I like John Cox tend to think that the change in winter synoptics may well be something that continues in winters to come and this winter goes down in my mind as a near miss. Should the next couple of winters continue the trend then a lot of the younger members may well enjoy a "winter of old" in the not too distant future.

    Link to comment
    Share on other sites

    Posted
  • Location: Redhill, Surrey
  • Weather Preferences: Southerly tracking LPs, heavy snow. Also 25c and calm
  • Location: Redhill, Surrey

    Steve

    Will read again when I get in but I think I have digested it. Excellent summary and I will post some thoughts later too. It will be interesting to see as we go through 06 whether we see a dominant GHP again...signals are that March will have this!?

    BFTP

    Link to comment
    Share on other sites

    Posted
  • Location: Dublin, ireland
  • Weather Preferences: Snow , thunderstorms and wind
  • Location: Dublin, ireland
    Steve,thanks very much for your review and the way thinks might develop in the years to come. For me the only disappointment has been the lack of snow in the North-East but the lack of winds and mild weather really made up for it I like John Cox tend to think that the change in winter synoptics may well be something that continues in winters to come and this winter goes down in my mind as a near miss. Should the next couple of winters continue the trend then a lot of the younger members may well enjoy a "winter of old" in the not too distant future.

    Morning Rollo/Tamara/PED/Noggin and all, (not forgetting Paul, see you on there)

    Steves post has already opened a great debate that will no doubt continue through to next winter and beyond.

    I think this was a nearer miss than most people realise.

    It would not take much for some considerable snow if that high had shifted a little further east. Like Steve said, pressure was nice and low down south which compares favourably to last winter, we also had that lovely cold pool over the continent. So we had a lot of the pieces in place but just missed the jackpot.

    Next year. :(

    Link to comment
    Share on other sites

    Posted
  • Location: New Ash green 150M / 500 FT
  • Location: New Ash green 150M / 500 FT
    Steve

    Will read again when I get in but I think I have digested it. Excellent summary and I will post some thoughts later too. It will be interesting to see as we go through 06 whether we see a dominant GHP again...signals are that March will have this!?

    BFTP

    Thanks BFTP-

    Some good comments already- from the usual Sources etc-

    Looking forwards to further contributions from you & the likes of the forecasting team / Gp et al'

    S

    PS Rollo- perhaps your heaviest snow to come this weekend....

    Link to comment
    Share on other sites

    Posted
  • Location: Dublin, ireland
  • Weather Preferences: Snow , thunderstorms and wind
  • Location: Dublin, ireland
    49? Wouldn't say I'm that far behind you fella! :) In fact, I feel about that this morning! As we said, our respective locations would produce a very different 'take'. The London area isn't great for much weather at any time of the year (unless it's unbridled summer heat you're after) so by that yardstick, it's been a remarkably bland winter. I do agree about the synoptics this year though, but no sooner do we get them then we get a rampant pacific jet that has scuppered any real enduring cold at almost every juncture. I just hope that the future is not a chilly, dry one.

    Hi PETD,

    I suppose folk down in the SE of the UK do get more "boring"`weather than we do but when you are more prone to extremes both hot and cold and there in lies the excitement of what the future may hold for you and I am mainly thinking about the cold.

    You should get a more continental influence over the next few years and this could produce some good snow events. :)

    This site which I used a lot over the winter quite quickly showed how close the very cold weather really was.

    http://www.awekas.at/en/uebersicht.php?nid=10

    Thanks BFTP-

    Some good comments already- from the usual Sources etc-

    Looking forwards to further contributions from you & the likes of the forecasting team / Gp et al'

    S

    PS Rollo- perhaps your heaviest snow to come this weekend....

    Hi Steve,

    Interesting the difference a few hundred mile makes. There you go, the continental inluence again.

    Looks exciting for you UK guys

    We Ireland will have much higher temperatures :)

    Link to comment
    Share on other sites

    Posted
  • Location: Abingdon - 55m ASL - Capital of The Central Southern England Corridor of Winter Convectionlessness
  • Weather Preferences: Winter: Snow>Freezing Fog; Summer: Sun>Daytime Storms
  • Location: Abingdon - 55m ASL - Capital of The Central Southern England Corridor of Winter Convectionlessness
    Given the synoptic patterns over much of this winter, are you not amazed that I've not seen one single day of lying snow? Really, just what will it take?

    Fantastic work by SM and the questions he poses are very valid. Certainly I have to agree with the conclusion that the upper Stratospheric temperatures appear to be pulling the strings. However, I am far from convinced that this will be repeated in forthcoming winters. Looking back over the long-term records reveals that the only weather pattern for the UK winters from indivdual winter to individual winter is that there is no pattern. I can see the hype and hysteria building already for Winter 2006/2007. I hope it's not going to be the mother of all letdowns.

    PATD raises a good point. If I'd been offered the synoptic pattern and temperatures for this winter last October, I'd have bitten your hand off. But I'd be astonished to be told, yet again, that I would not see any no proper lying snow in spite of this data. Remember, there's little consolation in 'almost' having a severe cold spell, in the same way as there's no reward for 'almost' getting an answer right on WWTBAM. The data looks impressive, it's just a shame one can't build a dataman, have a databall fight or go sledging on a layer of data.

    Link to comment
    Share on other sites

    Posted
  • Location: Horley, near Gatwick
  • Location: Horley, near Gatwick
    The data looks impressive, it's just a shame one can't build a dataman, have a databall fight or go sledging on a layer of data.

    Raised a distinct chuckle that one, Enforcer :)

    Link to comment
    Share on other sites

    Posted
  • Location: Skirlaugh, East Yorkshire
  • Location: Skirlaugh, East Yorkshire

    Very nice review by Steve and highlights that synoptics have been rather different this year to previous years. However the main problem we face until we are to actually get snowy weather out of these synoptics is cold pooling. The reason this winter has failed to live up to expectations with regards to snow is because we always seem to recieve the synoptics when there is no cold air around. The easterly 10 days ago was a prime example, it was far too marginal due to lack of cold air, while when the cold air is present, we are stuck in a westerly airstream which pushes it further away.

    In my opinion, if a change has occured, then we have only really got to 2nd base. To get the home run and "winters of old" we need cold pooling to be there at the right time, which in the last two winters, has been the real problem.

    Link to comment
    Share on other sites

    Posted
  • Location: Liphook
  • Location: Liphook

    Great post Steve!

    Something I noticed in Feb/March 05 was the strong northern blocking. So during last summer i decided to have a sneaky look back to the late 70's and saw that just like Feb/Mar 05, there was several intances of northern blocking in the winter period.

    so what I was personally looking for was another phase of northern blocking, and indeed at the same time as last year we got that in the shape of the easterly/northerly. It stil wasn't that potent but to be fair neither where the set-ups in the late 70's.

    What is also intresting is that just like then, we are exiting it seems a prolonged warmer period relative to what came before and the global patterns look very similar to me. the change in synoptic set-up is given even more credit when it comes at the start of the solar min period.

    Still, as Reef said the synoptics haven't really been given justice cimpared to what could be expected.

    But really, is that so suprising???

    We've had quite a few years of mild winters so it was always going to take at least 1-2 years to start to repair the damage of years of stupid warmth. This is the last few months have become rather intresting in terms of CEt, with 3 out of the last 4 having a below average CET in terms of the 71-00 series, though really 4 months isn't long enough to make a trend.

    Finally, when looking for the big one, it should be intresting to note that after the several cool down winters, we had the winter of 1978/79, and that time the easterly really was a beast:

    http://www.wetterzentrale.de/archive/ra/19...00219790215.gif

    http://www.wetterzentrale.de/archive/ra/19...00219790101.gif

    Link to comment
    Share on other sites

    Posted
  • Location: Abingdon - 55m ASL - Capital of The Central Southern England Corridor of Winter Convectionlessness
  • Weather Preferences: Winter: Snow>Freezing Fog; Summer: Sun>Daytime Storms
  • Location: Abingdon - 55m ASL - Capital of The Central Southern England Corridor of Winter Convectionlessness
    In my opinion, if a change has occured, then we have only really got to 2nd base. To get the home run and "winters of old" we need cold pooling to be there at the right time, which in the last two winters, has been the real problem.

    In my view it's a double-edged sword, due to precipitation being lacking on the few occasions when the air over the UK is cold enough for snow.

    If one takes a look at the monthly reports from winters past, one would see phrases such as:

    "A cold front swept down from the north bringing heavy snow across the country."

    "On 8th January there was heavy snow in Scotland. This transferred to Northen England on 9th. By 10th the snow had reached Wales and The Midlands."

    "A deep depression moving through the English Channel brought heavy snow to Southern Counties of England and Wales."

    A description of this winter might record snow events as follows:

    "A line of patchy scattered showers brought some light snow into the Midlands."

    "A keen easterly wind created overnight snowcover in hilly parts of East Anglia, Essex, Kent and East Sussex."

    "A northerly airstream gave accumulations in North Eastern Scotland."

    Everything has become much more localised.

    Link to comment
    Share on other sites

    Posted
  • Location: Lincoln, Lincolnshire
  • Weather Preferences: Sunshine, convective precipitation, snow, thunderstorms, "episodic" months.
  • Location: Lincoln, Lincolnshire

    The February 2006 chart shows some promise as Steve says, for it does resemble the charts from the 1960s. However, the Winter 2005/06 mean SLP chart paints a different picture:

    http://www.climate-uk.com/monpre/06QQ.htm

    This chart clearly shows a bias towards high pressure located to the north of the Bartlett position, and a strong northerly tracking jet. Rather than going back to the February 1960s pattern, it continues the pattern of continued northward movement of the jet, with south-east England now under the high that used to sit over Iberia.

    Philip Eden's charts actually show an even more clear-cut trend than I thought would be the case. There is strong evidence that winters are changing, and that we are probably moving into a new era of winters that may well be less mild than most of the post-1988 ones- but will they be cold and, eventually, snowy, or will they just be cold and very dry?

    The northerly tracking jet, I'm afraid, is one of the main reasons why cold pooling is less guaranteed than it used to be. If we have three weeks of tropical air being pumped into the Arctic and Siberia, the source regions will end up far less cold than usual. This winter has continued the trend for the Arctic, but increased blocking to the east has enabled the traditional Siberian cold pooling at times.

    Link to comment
    Share on other sites

    Posted
  • Location: Redhill, Surrey
  • Weather Preferences: Southerly tracking LPs, heavy snow. Also 25c and calm
  • Location: Redhill, Surrey

    We've had quite a few years of mild winters so it was always going to take at least 1-2 years to start to repair the damage of years of stupid warmth. This is the last few months have become rather intresting in terms of CEt, with 3 out of the last 4 having a below average CET in terms of the 71-00 series, though really 4 months isn't long enough to make a trend.

    Finally, when looking for the big one, it should be intresting to note that after the several cool down winters, we had the winter of 1978/79, and that time the easterly really was a beast:

    kw got this from Philip Eden

    Fred, I did something like this last week, but let me give you a more complete version which you can post if you like ... these are using all the averages I have handy.

    So the winter quarter 2005-06 (i.e. Dec, Jan, Feb) was:

    0.7 degC below the average for the last ten years, 1996-2005

    0.3 degC below the average for 1971-2000

    0.1 degC above the average for 1961-1990

    0.2 degC above the average for 1951-1980

    0.4 degC above the average for 1941-1970

    0.2 degC above the average for 1931-1960

    exactly equal to the average for the 20th century (ie 1901-2000)

    0.5 degC above the average for the entire CET record (ie 1659-2005)

    My view is that you can use any period you like as long as you specify what it is. But I do deplore the MO's unannounced and unexplained switch to 1971-2000 in their winter forecast verification, whereas they use 1961-90 on practically every other page on their site, and in practically every other press release or publication that they make. Crude manipulation if you ask me!

    Philip

    Look at the entire CENTURY CET! Anyway it sems temp wise this winter DID deliver. There is a real chance that winters may become less snowy...but oddly enough colder too. Also looking at the figures if we ran this winter to the 1900 to 1930 CET which I don't have what would we get? Below I would suspect and by as much as against the 71-2000 CET, I say this as note 41-70 was 0.2c colder than 31-60 and we know 20s and 30s were generally mild so what would that be? I suppose I'm saying there is no unparallel warming and I full heartedly expect we have now entered the next winter phase...what goes round comes round :)

    BFTP

    Link to comment
    Share on other sites

    Posted
  • Location: G.Manchester
  • Location: G.Manchester
    Look at the entire CENTURY CET

    Which I decided to work out. Here's the results;

    December 1900-2000; 4.66c. At the start of the century there were warm Decembers mixed with quite cold one's. Lately Decembers have generally evened out a bit. Warmest December 1934 with a CET of 8.1c and coldest 1981 with a CET of 0.3c. 1981 was the only year that contained a December below 1.0c.

    January 1900-2000; 3.93c. There were no very cold Januarys (CET below 1.0c) until 1940. Januarys upto 1940 were mixed with quite mild and quite cool. Apart from the record warm 1916, warm 1921 and 1932 there weren't many very mild one's. Lately Januarys have almost been entirely mild but you do however have to go back 96 years until you get a warm January (CET above 7.0c). Warmest January on record being 1916 (CET 7.5c) and coldest 1963 (CET -2.1c)

    February 1900-2000; 4.69c. Loads of very warm Februarys upto 1940...1903 (CET 7.1c) 1914 (CET 6.8c) 1918 (CET 6.5c) 1920 (CET 6.0c) 1926 (CET 6.8c) and many more mild ones with the CET between 5.0c and 5.9c. It was 17 years at the start of the century until a very cold one was recorded (1917 0.9c) also 1929 (0.4c) 1942 (0.1c) Lately February have been remarkably mild with 2002 (CET 7.0c) 1998 (7.3c) 1990 (7.3c) last time we had a very cold February were 1986 (CET -1.1c) and was also the second coldest February of the 20th Century and coldest month since 1963.

    So winter compared to the 1900-2000 average was;

    December; 4.3c (0.36c below average)

    January; 4.6c (0.67c above average)

    February; 3.6c (1.09c below average)

    Average winter for the 1900-2000 average (4.42c)

    Winter 2005/2006 in comparison (4.16c)

    So that's 0.26c below average.

    Link to comment
    Share on other sites

    Archived

    This topic is now archived and is closed to further replies.

    Guest
    This topic is now closed to further replies.
    ×
    ×
    • Create New...