It's that time of the year again - where we get to drool as normally warm places get heavy snow (and we don't).

So, to kick things off - hours of heavy snowfall in Tokyo (around 12 degrees below average). Until this morning it was just forecast to be rain at 4C, but it's been upgraded to snow in this morning's run.

http://www.metoffice.gov.uk/public/weather/forecast/xn76vrqe1#?fcTime=1479945600

 

But if it's any consolation, Verkhoyansk, in Arctic Siberia, one of the coldest inhabited places on Earth, hit 19.2c last Friday


http://siberiantimes.com/ecology/casestudy/news/n0793-no-global-warming-in-siberia-donald-trump/

So we probably don't want much Siberian air just yet

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UK Outlook for Thursday 8 Dec 2016 to Thursday 22 Dec 2016:

After an unsettled start to December, the rest of the month is likely to be calmer overall. High pressure is expected to dominate, especially in the north and east, leading to drier than average conditions. Interludes of more unsettled weather are expected to be fairly limited, though these could still lead to some snow. Whilst it may be relatively mild at times, temperatures on the whole through this period are likely to be below average.

Updated at: 1315 on Wed 23 Nov 2016

The latest METO update.Still sticking to its guns ie HP taking over after an unsettled start.They mention HP dominating particularly in thei the north and east.

Question where would HP centre be located -sometime to the north and sometime to the east  or generally to the north east.?The exact position has a huge impact on the temperature of the air flwing over us.

Another question when is the next METO contingency forecast due?

Another question when is the next METO contingency forecast due?

It usually comes out a couple of days before the end of the month so probably Monday or Tuesday next week. But it can vary.

Netweather's winter forecast is out

"Forecast Background

From the outset this has been an incredibly difficult forecast to work through, with multiple variables this season that are outside expected parameters. In essence, it is a winter where wildcards are in abundance.

Temperatures - Front Loaded Cold

During December and January, there is a greater probability (60%-70%) of colder than average conditions as high pressure systems become situated in, around and particularly to the north of the UK. This points to an increased risk of cold air masses originating from the north or east affecting the UK. A lower likelihood outcome is that temperatures during this period will be close to average, but even so, relatively cold conditions can be expected at times, and especially so when compared with last December and January. There is the potential for a change to milder conditions later in the winter, but this is an uncertain development at the current time.

Rainfall - Dry First Half, Potentially Becoming Wetter Later


The overriding signal this winter is for a greater chance (>75%) of slightly drier than average conditions during the first half of the season. This is due to the expectation of frequent high pressure and 'blocking patterns'. This signal is in contrast to last winter, with December expected to be very different to the exceptionally wet and windy December of 2015. There may well be a recovery in precipitation totals to nearer average through February and the latter half of the winter in general, but given the time frame involved this is an uncertain development, with a lower likelihood (>25%) of drier conditions continuing throughout the winter period."

http://www.netweather.tv/index.cgi?action=longrange;sess= 

All the best to Tony and Matt with that forecast, Tony doesn't have the best of records over the years (apart from predicting a couple of pretty obvious mild Decembers) when doing it with Chiono so we shall see how this partnership does.

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">http://www.bbc.co.uk/weather/features/38072856?ns_mchannel=social&ns_campaign=bbc_weather&ns_source=twitter&ns_linkname=news_central

The key word is "drier." than average.I have posted elsewhere that I think the most likely cold spell is mid December and marked by frost and fog rather than shed loads of snow.

In H.H Lambs classic book "The English Climate " written in 1964,he identified singularities being periods of weather that appeared more regularly than not. December split into 

Early winter storms  26/11-10/12  Winter return of the westerlies after autumn anticyclonic episodes.

December Continental Anticyclones  17-24 Dec -Before Christmas frosts dryest period of December.

Storms of Mid Winter  26 Dec.-12 Jan 

So December Continental anticyclone is the most likely weather type for  a possible winter cold pell this year.

It is also true to say that rarely is there prolonged prolonged snowy spells in December.Of course there was 2010 but before that only 1981 really had prolonged snow cover. Earlier than that  only December 1961 come to mind with a two week cold cold spell from around Dec 20th.

There are occasions when a cold snowy  spell set in around Christmas and then persists  into a cold January.Into this category comes December 62,December 78  and December 85.

 

December 1970 was a good snowy Christmas for me.
Do Lamb's theories hold up statistically in the last 5 decades?

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The key word is "drier." than average.I have posted elsewhere that I think the most likely cold spell is mid December and marked by frost and fog rather than shed loads of snow.

In H.H Lambs classic book "The English Climate " written in 1964,he identified singularities being periods of weather that appeared more regularly than not. December split into 

Early winter storms  26/11-10/12  Winter return of the westerlies after autumn anticyclonic episodes.

December Continental Anticyclones  17-24 Dec -Before Christmas frosts dryest period of December.

Storms of Mid Winter  26 Dec.-12 Jan 

So December Continental anticyclone is the most likely weather type for  a possible winter cold pell this year.

It is also true to say that rarely is there prolonged prolonged snowy spells in December.Of course there was 2010 but before that only 1981 really had prolonged snow cover. Earlier than that  only December 1961 come to mind with a two week cold cold spell from around Dec 20th.

There are occasions when a cold snowy  spell set in around Christmas and then persists  into a cold January.Into this category comes December 62,December 78  and December 85.

 

December 1970 was a good snowy Christmas for me.
Do Lamb's theories hold up statistically in the last 5 decades?

Bertwhistle I believe that original classification had some criteria for regularity of occurrence but i think that criteria related more to Germany (the Flohn and Hess criterion ) than the UK.

Given all the failures to find significant links between weather types and analogue years i doubt very much that  the is any significant link over the last five decades. Have a look at Appendix 1 of The English Climate and see what you make of it.!

I must say, after being quietly confident for this winter following early pronouncements by the Met Office & BBC, my faith is shot through now.

It's not because current NWP is poor (it flips about like anyway), but rather that the semi-permanent HLB which was forecast to be in place for the first half of winter at least and be the driver for feeding generally cold conditions to the UK is being shown to diminish to such a point it has little or no influence on the UK, whilst crappy lows just barge through at will.

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December 1970 was a good snowy Christmas for me.
Do Lamb's theories hold up statistically in the last 5 decades?

Bertwhistle I believe that original classification had some criteria for regularity of occurrence but i think that criteria related more to Germany (the Flohn and Hess criterion ) than the UK.

Given all the failures to find significant links between weather types and analogue years i doubt very much that  the is any significant link over the last five decades. Have a look at Appendix 1 of The English Climate and see what you make of it.!

Thank you Roger and sorry the quoting formatting doesn't seem to be working for me just now .

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I suppose it's easy to be downbeat after the last few Winters. But one has to remember that even in 2009-10 which was a brilliant Winter around here most of us didn't get a first covering of snow until the 18th December then heavier falls on the 20th & 21st which was still there past xmas day IMBY. Then it culminated in an epic January with over a foot of snow on the 5th & temps down to -17C here.

Already I have had a covering of snow last week which I didn't get in Nov 2009, wasn't much mind, just a light slushy covering but it was better than nowt. I think the middle of Dec could be decent. Hopefully a taste of Dec 2009 and a very seasonal run up to xmas. But at the end of the day the weather will do what it wants. I won't lose sleep over a mild Winter as it is beyond my control but a cold one I much prefer!

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Yes 2009/10 was excellent here. Snow lay from the 17th December and lasted for 30 days at sea level. The river began freezing for the first time since 1995. Inland at my family home at 100 Mtrs asl there were 75 snow lying days over the Winter with the best falls being 40 cms on the 27th Decmber and 30 cms in late February.
Meanwhile this year it looks like a UK high may well be in place in mid December. Ok dry and cool but a waste of possible snow time by that time of year if it hangs around.

I suppose it's easy to be downbeat after the last few Winters. But one has to remember that even in 2009-10 which was a brilliant Winter around here most of us didn't get a first covering of snow until the 18th December then heavier falls on the 20th & 21st which was still there past xmas day IMBY. Then it culminated in an epic January with over a foot of snow on the 5th & temps down to -17C here.

Down here we didn't get anything till January that winter....   Think there may have been some sleet one day between Christmas and New Year ....

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Someone posted that recent winters have seen the really cold weather going off down to Greece and the Med, instead of staying north where it 'belongs'. (might have been in the model thread - can't find it now)

Anyway, here we go again

http://www.wxmaps.org/pix/temp4.html

 

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So here’s my final prognosis on the upcoming Winter 2016-17.

I’ve used 6 different indices to try and determine the Winter outcome, these being ENSO, Solar cycle, QBO, North Atlantic SST profile, PDO and the November 2016 synoptic anomalies. I dropped two other elements, (1)the October synoptic anomalies, because there were only 2 matches overall !!, and (2) the October AO index, again because there were too few decent matches. So from all these, here’s my thoughts:

December 2016
What I found striking was that all indices are pointing to a High Pressure anomaly in the mid-Atlantic and towards the Azores, with a chain of Low Pressure anomalies stretching from Iceland to Scandinavia. So, Low Pressure areas are likely to swing down from near Iceland on a NW-SE trajectory, and occasionally bringing some colder interludes, especially for the NE of the UK. However, due to a dominant W-SW flow, December looks to be slightly milder than average, and also a little drier than average too.

January 2017
The general theme seems to be an encroachment of the Russian High westwards somewhat, and also a build of High Pressure over the Arctic, although no major blocking is indicated. Some signals also for a weak Low Pressure anomaly over Europe, and still a mid-Atlantic or Azores High signal, though less strong by then. The net result looks like being a near average month for both rainfall and temperatures, with no one weather type dominating this month. Probably a real mix of Atlantic spells, some Anticyclonic set ups, and the risk of a few colder spells from the north and east.

February 2017
This is where there is a definite divergence of what the indices are suggesting. In fact there is a straight two-way split between what the Oceanic indices are indicating (ENSO/PDO and Atlantic SSTs), and what the Solar/QBO and November analogues are saying. So we have the Oceanic indices suggesting a fairly benign February with a lot of High Pressure stretching from the mid-Atlantic, through to the UK and into Northern Europe, giving us a fairly settled, dry, and near to average month for temperatures. However the other indices suggest more of a Northern High Pressure block setting up, Low Pressure over the Med, and with a definite easterly anomaly into the UK resulting in a colder month. On balance, I think it will be more a mix of the two scenarios, but perhaps more favouring the benign option. That still gives us a February with a decent chance of some colder, wintry weather, but probably for much of the time, February will be fairly uneventful, settled and dry with temperatures near normal.

WINTER 2016-17 SUMMARY
The Winter overall is likely to be near average to slightly mild, and with rainfall a little below average generally.

 

 

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Mainly dry this week as we move into winter with cloud amounts probably increasing - no hints of anything colder long term unlike that past 5 days or so

http://www.bbc.co.uk/weather/features/38122653 

I've issued my full winter forecast on my blog. Here I'll just post my thoughts for each of the three winter months:

December

Out of all three winter months, I am forecasting December to hold the best chances of colder weather for the UK. It appears as though this month could actually be a very anticyclonic month, with an area of high pressure centred quite close to the UK. Of course at this time of year, this would produce cold conditions at the surface due to temperature inversions. This means that many parts of the country will see a fair amount of frost and fog this month. Furthermore, this means that I also predict the month to be rather dry.

It is also worth noting that there is a chance that this high pressure system could possibly move westwards out into the mid-Atlantic, on some occasions. This would have the effect of bringing a northerly wind down across the country, which could increase the chances of snow and harder frosts, even for southern areas of the country.

January

I am forecasting January to be somewhat of a transitional month, with colder conditions being more dominant in the first half, before more of a milder Atlantic flow increases in the second half. In terms of individual weather, this means that this month could actually be very varied. There is the potential for some cold and snowy weather early on, followed by an increased chance of more stormy weather later on. I expect temperatures to overall come out very near to average, with northern areas being more prone to colder conditions and more southern areas being milder. Rainfall, I predict to be very near average in eastern and southern areas, whilst northern and western areas will see the wettest conditions.

February

Obviously confidence does naturally fall away for later in the season, but as of current, I am expecting February to be the mildest of the three winter months. Here I expect any UK blocking to collapse into Europe and for a predominantly west-to south westerly flow to set up nationwide. In February I expect both temperatures and rainfall to be above average especially for northern and western areas, with south-eastern areas seeing the driest conditions, closer to the Euro high. I also wouldn’t rule out some northern areas seeing some potentially stormy weather at times.

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Mainly dry this week as we move into winter with cloud amounts probably increasing - no hints of anything colder long term unlike that past 5 days or so

http://www.bbc.co.uk/weather/features/38122653

This looks like the same forecast that was shown on BBC1 at around 1:15pm.

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Mainly dry this week as we move into winter with cloud amounts probably increasing - no hints of anything colder long term unlike that past 5 days or so

http://www.bbc.co.uk/weather/features/38122653

Somewhat ironic when the only text associated with the forecast states, "A week of dry and cold weather is expected in the days ahead, but there might be a twist with in."

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Down here we didn't get anything till January that winter....   Think there may have been some sleet one day between Christmas and New Year ....

To be fair, that was the December when snow kept causing widespread pre-Christmas transport chaos throughout the south and south-east, trains stuck in the Channel Tunnel, steam train to the rescue, M25 gridlocked, "where were the gritters?" etc.

And January was worth the wait down here in Somerset. 6 Jan. 2010:

Back to 2016-17, and I gave the lawn an extra final mow this afternoon, and I'd only be doing that if I thought there were a chance of snow. Important when you live only 32m above sea level, as I do now unfortunately, 'cos you're never going to get more than an inch of snow at that altitude, and you don't want any green bits poking through to spoil the effect.

I just have a feeling in my water that the coming frosts from high pressure centered over us might give way to a bit of lying snow if the high drifts north while the ground's still cold. The overall set-up doesn't look like your normal one with a powerful jet nailed on to sink the high instead. 

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 SUMMARY – TEMPERATURE: During December below-average temperatures are more likely than above-average temperatures. The risk of impacts from cold weather is considerably higher than normal. Predictions for UK-mean temperature for the whole of the winter season (December-January-February) show only a slight shift from the normal range of expected conditions. Nevertheless, this unremarkable outlook conceals a change from an increased risk of a cold start to winter to a greater likelihood of milder conditions later on. These different phases tend to balance the probability of above- and below-average conditions in the overall 3-month average, but the risk of cold weather impacts in the first half of winter is considerably greater than normal. Overall, the probability that the UK-average temperature for December-January-February will fall into the coldest of our five categories is between 20% and 25% and the probability that it will fall into the warmest of our five categories is around 15% (the 1981-2010 probability for each of these categories is 20%). As stated above, however, these statistics conceal a shift in probabilities as winter progresses. CONTEXT: Sea surface temperatures in the tropical Pacific Ocean remain slightly cooler than average, close to the threshold for a La Niña event. While temperatures imply a ‘neutral’ state of the El Niño-Southern Oscillation, tropical Pacific rainfall patterns do appear to be similar to those expected during La Niña. Relatively little change is expected in the coming months. Weak La Niña conditions slightly increase the probability of blocking over the North Atlantic and Europe in early winter, but slightly increase the chance of more mobile, westerly weather in late winter. This would imply a shift in likelihood towards colder- and drier-than-average conditions for the UK early in winter and the reverse later on. The Quasi-Biennial Oscillation (QBO), an oscillation of the equatorial winds in the stratosphere, remains in a westerly phase. The QBO influences winter conditions over Western Europe by modulating the strength of the stratospheric polar vortex (SPV) and thereby the phase of the North Atlantic Oscillation (NAO) at the surface. The westerly phase of the QBO tends to favour a stronger SPV, particularly in early winter, leading to a higher likelihood of a positive phase of the NAO. Despite the westerly QBO, the SPV is actually much weaker than normal this year and is expected to only slowly strengthen during December. A weak SPV tends to influence surface conditions with a delay of a few weeks. This implies an increased likelihood of negative NAO and blocking during December and January, which would increase the probability of cold weather in the UK during this first part of winter. Arctic sea ice extent is at a record low level for the time of year. The largest sea ice deficits are in the Barents and Kara Seas. Recent research suggests that lack of sea ice especially in the Eurasian sector, may increase the likelihood of blocking patterns and the negative phase of NAO occurring in winter. In the North Atlantic Ocean, sea surface temperatures are well above average in the western Atlantic near Newfoundland. This pattern of sea surface temperatures is thought to moderately increase the probability of above-average pressure in the central North Atlantic, leading to an increased frequency of northerly or northwesterly winds over the UK. At this time of year such a pressure pattern is often associated with below-average temperatures. During December, the factors described above suggest an increased likelihood of negative NAO and blocking, which usually bring below-average temperatures for the UK. Predictions from the Met Office seasonal prediction system, along with those from other global forecast centres, offer strong and consistent support for this view. The left-hand graph in figure T2 shows a clear shift towards colder conditions. The chance of a prolonged spell of cold weather taking hold in December is high compared to normal, although more usual types of winter weather are not ruled out. winter, pThrough the early part of the 3-month period, colder-than-average conditions are more likely than milder-than average. Later in the particularly into February, prediction systems signal a shift towards less likelihood of blocked weather patterns, which would imply a reduction in the chances of cold conditions. The effect of these different phases is to bring probabilities for the 3-month UK-average temperature into closer balance. Therefore, the right-hand graph of figure T2 does not tell the whole story and it should be emphasised that in the first part of winter the risk of cold weather impacts is considerably

Met Office three month forecast -with exciting bits bold!No detail on any snow fall but key sentence"  the risk of impacts of impacts from cold weather is considerably higher than normal"