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reef

The Winter 2011/12 Forecast Thread

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Due to the number of winter forecasts this year it has been decided that we'll have a dedicated thread where all of the forecasts can be placed instead of having several individual threads in the forum. That way we keep them all in one place and come the end of winter can see which forecast/method proved the most successful.

If you have a forecast for the winter or just want to comment on an existing forecast please feel free to post in this thread.

Roger J Smith

Winter Forecast for 2011-12

Methodology

My forecast continues to use natural variations as the main foundation, but this season I have brought daily CET data on stream replacing monthly data for the first time. I am hoping this will lead to an increase in accuracy and fine-tuning of the forecast. Essentially, the forecast is generated by isolating several dozen cycles of various lengths, all of rather small amplitude when considered in isolation. These also have directional parameters -- some of the variables are retrograde, helping to set a pattern for the forecast in terms of blocking and air mass origins to complement the basic numerical output. The technique has given mixed results but has in the past three winters identified most of the colder periods with considerable accuracy. The most recent summer forecast, while somewhat off the mark in calling for slightly warmer than average, was closer than many other approaches. Last winter there was a generally good review for the forecast to late January but we expected the cold to return in February which it failed to do. When I say "we" the reference is to my long-time collaborator in long-range forecasting and research, "Blast from the Past." Fred has reviewed this forecast and gives it a general endorsement, but would like to confine his forecasting to 4-6 weeks this winter season due to heavy workload. He will drop into the thread and give some updates from time to time.

Returning to methodology, the numerical output includes some variables based on lunar orbital cycles (although this is about 20-30 per cent of the variability in the research model) and this input assists in timing various events or spells of weather. Other input tends to establish longer-term pressure signals and flow patterns. The blend gives us numerical output that could be used to create even daily-scale model maps but at the current level of validation, I prefer to use this blend to give just an indication of the sort of rhythm of weather events at different stages of the winter season. In any case, a long-range forecast is mostly useful for establishing tendencies and ranges of possible impact and not in nailing down events that can be refined closer to time anyway.

General Forecast Statement

The winter season appears likely to be cold again, at least on balance, but unlike last year, January may be the most wintry month of the three. The very basic overview is for a rather cold November, a variable December near average overall, a cold and potentially snowy January, and a mild February, followed by a "backward" March that has a return to rather wintry weather later in the month. For reference, CET monthly temperatures are predicted at 5.8 for November, 4.5 for December, 1.5 for January, 6.2 for February, and 6.5 for March. Precipitation is expected to be generally 25-50 per cent above normal except for pockets near normal in the south and east. Snowfall is expected to be above normal almost everywhere with several wintry periods expected.

The detailed outlook

From what will evidently be a cold period in late October, expect a recovery to mild weather for a while in early NOVEMBER, but progressively colder weather mid to late month with some early signs of winter in northerly and easterly outbreaks. Some frost days may occur in central and northern regions but unlike last year, this late November cold is not expected to dig in and produce a lengthy cold spell.

DECEMBER may be a roller coaster of mild and cold spells. The coldest part of the month is likely to come around the 15th to 20th. Before that, the first two weeks may include some strong winds from deep Atlantic lows, heavy rainfalls, brief intervals of hail or snow, but eventually, arctic air should develop and there could be snow on the ground at times just before Christmas. Then the Christmas holiday period is expected to turn milder with fog and rain especially around the 27th when it could once again become rather stormy. By New Years Eve it may be turning a lot colder.

JANUARY may be "the" month for this coming winter, and there may be several occasions with snow although the first week to ten days may start with more of a northwest flow that would restrict snow to western and northern regions. This could be a windy period in general before deeper cold arrives probably from a Scandinavian high. This should direct the winds more easterly and give the higher snowfall potential in central and eastern counties. Severe frost may develop and the CET estimate (1.5) is conservative depending on snow cover feedback, but frost days seem very likely around mid-January. There may be further snowfalls later in the month as the storm track tries to push back north.

FEBRUARY could start out cold and snowy but the model output shows a strong warming early in the month and a peak of very mild conditions in mid to late February. This suggests that southerly flow may predominate and reverse the cold pattern to mild or even very mild. It may be rather dry in this pattern for the south and east, trending to wet in western Scotland and Northern Ireland.

MARCH is expected to start out mild but become a "backward" sort of early spring month with returns to wintry patterns later on. The below normal trend may deepen into early April. The warmth of April 2011 may be in contrast to a cold April in 2012 with May the warm month this time.

I will of course update this forecast if different indications are given from more reliable time scales, but this is what the numerical output shows at present. You could think of this method as being similar in concept to the CFS system although using (presumably) different input. As always, we hope for the best and consider "success" to be fairly loosely defined in terms of being more often right than wrong, or on the right side of normal two-thirds of the time.

A Few Other Notes

This winter, the lunar perigee falls about halfway from full moon to new moon or during the descending phase of lunar declination. This has in past analogues been associated with temperature reversals from mild to cold as the southward pull of the Moon towards southern max (at winter new moon) is enhanced. This is one reason why a lot of the colder intervals in the forecast are essentially lined up around mid-month although this period is only 28 days. The energy levels this winter will vary from an active phase lasting 5-6 days to a low-energy phase lasting 8-10 days. This may show up in a modulation of stormy weeks followed by blocked or inactive weeks. It's one reason why I suspect the main theme of the winter before any severe cold in January may be "from one extreme to the other." We may be reading a lot of comments in discussions about how the season cannot "make up its mind" and settle into one pattern. For those who like their winters active, this should be a good thing. For those who like cold and/or snow, patience may be necessary but January should deliver this time.

I think that in such an active pattern, a major windstorm seems a fairly good bet. While not wishing to be too specific, periods around the December and January full moons are favoured for strong westerly winds.

My advice to people in weather-sensitive areas of the economy would be to plan for a severe winter or at least a more severe winter than average, but not to expect it to be non-stop, there will be relaxed spells between wintry blasts. Some of the more extreme conditions in January may be harsh in isolated higher regions of the country. Livestock may need to be indoors or provided with extra feed at times. Road travel may be disrupted about 5 to 10 per cent of the time outside the more temperate south. There is a good chance of seeing four or five significant snowfall events and one or two major events possibly blizzards in some cases.

So now we wait ... and watch.

Backtrack

Backtrack's winter forecast 2011

Hi everyone. This forecast has been created from the trends and patterns of numerous model outputs ranging from the GFS,ECM,CFS and a couple of other factors too. Please don't slate my forecast if it does not show what you would like to hear, I have put a lot of hard work into creating the forecast and think you will find it fairly accurate up until January at the least. At this stage confidence falls drastically, with January looking likely to go either way at this stage.

My confidence in February is surprisingly high, not just based on the CFS anomaly charts' trends, but also due to the fact that I believe we are long over due a cool February. And whilst weather doesn't follow a set of rules, I certainly cannot see this month being mild at the very least.

Hope you enjoy reading it, sure I'm an amateur and you will find that RJF's forecast and BFTP's (when he does his) forecasts are likely to be much better, but hey, it's all in good fun!

Also, on a side note, I am a massive coldie fan, and writing the forecast for the first 2 months was painful for me, not only am I confident in their accuracy, but I am unfortunately expecting little cold for Western areas for some time. I've spoiled it enough. Good luck. smile.png

October:

21-30th - This period is likely to be mild and windy at times with the best of any brightness in the East, with the West seeing cloudier conditions with rain, heavy at times. Temperatures remaining around average for the time of year, perhaps slightly above average at times in the far South.

November:

1st - 10th - Numerous outputs, trends and patterns point to a North/South split during the first third of the month. It's looking very likely that it's going to be very average in the North, day time temperatures hitting 8-10C, but above average in the South, temperatures hitting 13-16C. Precipitation wise, the first start of the month looks like being very wet and unsettled, perhaps making up for the drought in place in Eastern areas. An Atlantic dominated first third, night time temperatures unlikely to bring any frosts at all away from the coldest of hollows.

10th - 20th - This period will follow the same theme as the first third for a time at least, with temperatures being pleasant enough in the South for T-shirts to be worn. In the North though, it's again very average for the time of year until the mid month point at least. Temperatures again 8-10C, 13-15C in the South. It's the mid month point that may bring some interest to you with the first frosts of the month likely, temperatures still recovering to average by day. This third is likely to be the windiest with frequent gales, especially in the West.

20th - 30th - Another dissapointingly average period with little in the way of Winter to be shown just yet. Temperatures again remaining oh so average, although temperatures may be down a little way at least, 5-9C in the North, 10-13C in the South. Rainfall should be around average for the time of year, as should sunshine amounts. A cold spell is likely around the end of the month (The very end of the month) giving the first low level snow to Northern & Eastern areas, this may also mark the start of the Cairngorm skiing season. Frosts are also likely towards the end of the month, but Western and Southern areas are going to have to wait to see anything remotely in the way of snow.

CET - 7.7C

December:

The first third of December will be dominated by a North Westerly flow, bringing Western Scotland, Northern Ireland, Wales and Western England their first snows of the season. The cold spell will not be anything remarkable with temperatures still managing to climb to 2-5C during the day, any lying snow is likely to be short lived, with hail showers becoming a very dominant feature for Western areas during the period.

The second third is likely to me average with little snow away from the highlands. Rainfall and sunshine amounts are looking around average, rainfall slightly above.

The Christmas period is a great day to feel the full effects of Winter as Santa makes his way down your chimney to make many boys and girls happy. Unfortunately santa may melt in England, as there is likely to be no snow away from the hills. For Northern Scotland, a white Christmas is looking likely with snow actually falling on the day!

The last 5-6 days may see the return of Northerly winds but confidence in this stage is very low. A North Easterly lasting 4-5 days seems the most likely scenario at this stage with snow showers for Eastern areas in particular.

CET - 5.4C

January:

January is likely to be a cold month. Where as December will struggle to get any decent frosts, there will not be a shortage of these in January as high pressure takes control of our weather for a time at least, bringing some painfully low night time minima, and temperatures struggling to make average during the day. Sunshine amounts are likely to be above average, where as rainfall is looking likely to be below average.

Snowfall throughout this period is going to be a premium.

The second third is when things start to get interesting. We start with winds switching to a morth North Westerly element, and as the week goes on, they switch around to North, followed by North East. This is likely to be the snowiest period, with much of the country seeing a good total of snow by the time the spell has finished around the 20th.

The last third is looking increasingly Atlantic dominated, with rainfall above average, and sunshine at a premium. Snow over Northern hills.

CET - 3.5C

February

February will see Winter in full force, with frequent cold spells and snow for many. Frequent Easterly winds will bring some impressive totals to Eastern areas, with the West having to wait a while to see anything wintry other than frosts.

The second period is likely to keep the Easterly theme going but perhaps snow showers for the West as the wind kicks in, sending the showers over the Pennines.

The last half is likely to be Atlantic dominated with frequent gales and above average rainfall.

CET - 2.9C

Overall an average Winter is looking likely. Nothing like the last 2, with the overall CET likely to be bang on, or VERY slightly below average.

Thanks,

Backtrack.

Radiating Dendrite

Winter Forecast:

Current state of play:

Low Solar Activity (compared to what has been the case during previous cycles). Activity is increasing though as we build up towards the maximum, but despite this I believe that a lag effect is experienced and the build up in activity will not influence the atmosphere until later on next year. With this in mind, the troposphere will continue to be cooler than normal; this it is believed leads to a greater frequency of Northern blocking and a more southerly tracking Jet Stream.

QBO is currently negative and east based (this strengthening) with a Negative QBO tending to lead to increased blocking, and colder weather through the January and February winter months. However, recent models have shown it may become less easterly with time through the winter, possibly becoming positive as well. A positive QBO which is west based is usually associated with boosting the La Nina, generally leading to a milder end to winter, with a more active Atlantic with increased zonality.

La Nina is predicted to strengthen during the winter, but should not become as strong as we saw last winter, as seen in the chart below:

As we can see though, this is not “nailed”, with the strength still ranging from strong to weak, depending on what models you look at. I think the only sensible thing to do is use the average for this forecast and base any predictions on the average that is currently being shown/predicted.

CFS model data is currently showing a mixed winter, with periods of high pressure dominated weather, as well as low pressure dominated weather and a more active Atlantic. The CFS shows a colder January at present with blocking in the mid-Atlantic during the first half of the month:

This is broken down though, with a trough establishing itself over Scandinavia during the second half of the month:

NAO/AO I believe are influenced by the factors laid out above, being reactive rather than pro-active when it comes to having an influence on the atmosphere and weather. As seen below both are slightly positive for the current month

October NAO +0.27

October AO +0.18

Early last winter saw both become strongly negative, to record levels in some instances, with strong Northern blocking developing during late November and December. Current values would indicate a mix or blocking as well as cyclogenesis in the Arctic and Atlantic, this being what is currently being shown in the GFS and ECM, with neither gaining a firm grip and the UK in a no mans land situation. I believe that we will see a negative NAO and AO during winter, in response to the lower solar activity lag, however, the figures will not be as extreme as what occured at the beginning of last winter.

Other minor factors:

Building Blocks - As has been discussed in the MOD thread, we do currently have a European high in place and a sluggish Atlantic stalling against this. Is this a theme that will continue to occur in winter?

Recent Past – With the last three winters containing significant cold spells, have we now turned a corner and finally rid ourselves of the modern winter curse that seemed apparent in the 90s/00s?

NH Snow Cover – Currently around average, however, sea ice did reach the second lowest extent on record, will this have a major impact?

Personally, I see these other factors as more minor in the development of winter than the teleconnections discussed above. However, the development of favourable synoptics during late autumn and increasing amounts of cold pooling are certainly a good thing if a cold winter is what you are looking for, however, this does not mean that a cold winter will be the end result, if the overriding back ground signals are not favourable.

So……..what do I expect from the winter?

CET Predictions??

November 7.0c

I see November as being a fairly benign and average month. We will continue with the theme of a high to the east and Atlantic troughs to the west during the beginning of the month, with the second half of the month seeing a more mobile Atlantic, with the high slipping into southern Europe, giving us a feed of SW winds for a time. Temperatures will be slightly above the long term average, with rainfall around average, perhaps above average in the North and West.

December 4.4c

December will start where November left off, with temperatures slightly above average and a succession of weather fronts crossing the country. By the middle of the month I expect the Atlantic to start to become quieter, in response to the Negative East based QBO and cooler troposphere. High pressure will start to develop, possibly from the west, with it becoming stationed over the UK as we move towards the Christmas period. I see Christmas as being quiet and anti-cyclonic with some cold nights and chilly frosty days. At the end of the month, we will start to see retrogression of the high away from the UK.

January 1.6c

I believe that January will contain the core of the winter cold, similar to what we saw in winter 09/10. Currently the CFS shows high pressure located around Iceland during the first half of the month:

As we can see, this would bring cold NE winds to the UK and snow. Although I agree with the signal for High Pressure, as shown by the CFS for this period (carrying on the theme from the end of December) I believe that we could see a significant high pressure cell forming over Scandinavia, having retrogressed from the UK and linking up with developing high pressure over Iceland and SW Greenland. This would see significant cold for the UK from the east, with the low pressure undercutting the high, with a southerly tracking Jet Stream. The CFS shows a breakdown during the latter part of the month:

I would agree with this breakdown, but I think that we will have a period of cold zonality as is shown above, with Northerly and North Westerly winds. January will return the coldest CET of the winter, potentially significantly cold, though this depends on the depth of the cold during the early part of the month and whether any unsettled weather at the end cancels this out to a certain degree.

February 4.4c

February I see as quite a mobile month (unusually so) in response to a slight strengthening of La Nina and the QBO becoming more west based and less negative. I see February as fairly average temperature wise, with blocking struggling to establish itself to the North. A mid Atlantic high may develop during the middle of the month (currently being predicted for March by the CFS as shown below):

This has the possibility of bringing some colder weather from the North, but I do not see it as a permanent feature, possibly slipping to our South West, with lower heights developing to the North.

Winter Overall 3.5c

Isolated Frost

Based on hunches, expectations and pattern matching...

December: CET 4.3C Cool, quite wet and Atlantic dominated.

Cool, generally wet, especially in the north, much of it falling as snow. High pressure in Greenland persists with a stable, repetitive Scandinavian trough. Jet to the north of the UK as lows move across Scotland, but a blocked atlantic, with limited slugglish energy, pulling in cool air from the north, but moving in from the north west/west. Heavy snowfall events across western parts, generally cloudy and cool across eastern areas. Turning milder as high pressure moves in from the west, with low pressure flowing across Iceland towards the arctic. Towards Christmas and New Year, cold westerlies move back in as high pressure sinks, and wet, windy weather for the north. Some limited snowfall, and some frosty spells in the south in the last week.

Pressure anomalies -12mb Reykjavik, +2mb London, +4mb Paris, -7mb Oslo, -2mb Berlin.

January: CET 2.4C Highlight of the winter for some - generally dry after a wet start.

Cool, becoming very cold, and very dry in parts. High pressure grows again in Greenland, and the jet moves south slowly towards Britain and France - this makes for a wet start over England and Wales. Mixed with atlantic airmasses of tropical and polar mixing. Becoming very cold mid-month as the arctic floodgates are opened. Very snowy at times for northern parts, bitter cold persistently - Polar lows move in to create immense snow amounts in some western parts. Very cold and dry in southern areas again. High pressure moves in from Greenland, ridging likely, giving a milder end to the month, but still generally below average - cold, dry and frosty in northern parts, more average and cloudy in southern parts.

Pressure anomalies +5mb Reykjavik, -3mb London, -7mb Paris, -4mb Oslo, 0mb Berlin

February: CET 5.0C Extremes of attempted easterly cold to warm, sunny spells.

The month begins with high pressure in charge, and a cool flow - generally dry and sunny. Soon, pressure begins to build rapidly in the Arctic, pushing south towards Scandinavia, as the jet tries to move north. Cold air pummels through Northern and Central Europe through the middle of the month, and record cold near Germany and Denmark. Quite milder towards Britain with a southerly flow as pressure towards the north west drops once more. The scandinavian high influences the British weather slowly towards mid-late month as cold -15c uppers reach the North Sea, but they are limited by a growing Atlantic presence. They give some wintry/snowy showers to the east for a while before being ousted by an increasingly strong atlantic. Some very heavy snowfalls in the midlands and south from battleground snowfall. High pressure generally moves in from the south/southeast late in the month as the first signs of warmer spring-like weather appear. A very warm, sunny end to the month with some westerlies and wetter weather for the north, but mostly dry and sunny, especially in the south.

Pressure anomalies -8mb Reykjavik, +8mb London, +7mb Paris, +4mb Oslo, +10mb Berlin

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Thanks. Interesting seeing them together and tends to suggest that January is going to be the most wintry month, consensus being ealier in the month but with some support for it being later.

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Positive Weather Solutions (PWS), a UK-based long-range forecasting agency has issued its long range forecast for Winter 2011-12.

The forecast, which covers the period December to February, indicates that a lengthy period of severe weather similar to that experienced in December 2010 is unlikely to be repeated.

PWS says parts of northern and north-eastern Britain “retain the best chance of experiencing a White Christmas”.

December temperatures are forecast to be around average for the time of year, while PWS says the prospect of prolonged wintry activity in January looks unlikely. The forecasting group said there is no strong signal for any widespread period of sustained cold in February.

Winter 2011-12: Occasional Wintry Weather, Often Dry in South

December – often cold, chance of snow in places

The start of winter is expected to present some contrasts for much of the British Isles. There are signals for some wet and unsettled weather over many western and a number of areas to the north. There is also strong evidence during the month for some chilly but mainly settled weather, with possibly severe overnight frost, along with persistent fog in low-lying localities. It is furthermore likely that a definite wintry episode will become established, with the potential for snow especially over areas of the North and East. Within this general circulation, some parts of northern and north-eastern Britain retain the best chance of experiencing a White Christmas. Temperatures will overall be on or slightly below average for the North, on or slightly above average for the South. Precipitation is likely to approach the long-term December norm, though some southern areas in particular may reflect notably drier than average values.

January – some cold, dry South developing

The first month of 2012 looks like being characterised by a sometimes mild North, and developing dry, at times colder conditions in the South. As a result many northern regions will often experience breezy, cloudier and wet weather but also some chillier, showery interludes – some of which will be wintry in nature. The prospect of prolonged wintry activity looks however unlikely, although occasional colder cells embedded within the overall flow will provide the North, especially upland districts, with temporary snow cover. Strong winds may also be a feature for these regions. Drier conditions, with some sunshine but overnight occasionally severe frost will be more frequent in the South. Some southern and eastern areas will witness cloud or fog formation, at times persistent, giving an overall cold feel. January’s temperatures will approach the norm or exceed it in some northern and western parts. Southern and eastern areas may be drier than the average.

February – generally milder

There are indications that February over the British Isles may initially offer some of the most unsettled weather of the entire season. Contained within this fairly disturbed pattern there are hints for occasional episodes of colder, polar maritime air moving across northern parts of Britain and Ireland in particular; this will bring sleet and snow, most especially to upland areas. There is however no strong signal for any widespread period of sustained cold. Spells of rain coupled with strong to gale force winds will also feature during February. The month will also feature some drier and pleasantly sunny passages, these most likely as the month progresses and across southern regions and the South-West in particular. Temperatures overall for the month are likely to be on or above the norm, perhaps notably so for parts of the South; rainfall also looks set to reflect on or above average values.

Commentary

Ray Anthony, Chief Assistant Weather Forecaster for PWS stated: “The PWS Wintercast 11/12 will now be assessed, reported and probably elaborated upon by British and Irish news media: some will do this fairly, others less so. The media, particularly its written variant, is in that tricky business of sourcing stories that raise profile and sell copy. Just how newsworthy is an often mild winter? Less energy consumption, less winter garb… this is not going to drive national economic recovery is it? January and February will nevertheless have mild passages, and the west looks on the whole well favoured in this regard.”

“How newsworthy is a wet winter? It’s not pretty, and wouldn’t offer any great drought scenario… but for some it will periodically be quite wet. Again the west and, at times the north, look fairly well set for rainwater. It may even be wet enough somewhere, at some time, for some flooding – hey, there’s some news – no real clues yet though. But, despair not. Some disruptive snow there will be – most likely in December across a number of regions. There will also be some uncomfortably expensive cold, most especially in northern, central and eastern areas and particularly during December and January: Very bad co-incidence with many of the areas and communities that are feeling most acutely the current economic negativity.”

PWS website link

The UK Met Office last week distanced itself from recent media reports that the UK and Ireland are set for an ‘Arctic Winter’. The UKMO, which stopped issuing seasonal forecasts in 2010, also has said that recent long range forecasts by other agencies “bear no relation to the kinds of weather that forecasters at the Met Office are currently expecting”.

iWeather Online (IWO) also has forecast that Ireland and the UK are unlikely to see a repeat of the pre-Christmas freeze of 2010. Temperatures are expected to remain below average for much of the coming season, however, according to the IWO forecast.

In an opinion piece for The Times, UKMO Chief Executive John Hirst called for a sense of reason in response to the claims (read 1, 2, 3) of other forecasting agencies in weeks.

According to the UK Met Office: “Over the past few weeks, there have been some colourful headlines in some parts of the media about what’s in store for this year’s winter in the UK. Reports of ‘-20C within weeks’, ‘A winter fuel crisis on the way’ and ‘Widespread snow in October’ have all raised expectations that we’re in for an ‘Arctic winter’. [These headlines] bear no relation to the kinds of weather that forecasters at the Met Office are currently expecting – there is no need for alarm.”

Last month, a UK-based long-range weather forecaster issued his prediction of an early start to winter 2011-2012 for many regions of the United Kingdom and Ireland. James Madden of Exacta Weather forecast heavy snowfalls in places as soon as late October and early November.

World Climate Service (WCS), a joint venture of Prescient Weather Ltd and MeteoGroup, said it expected the coming winter to be dominated by a negative phase of the NAO, resulting in colder, dryer, and less windy than average weather on the British Isles, in France, Germany, and the Nordic and Baltic countries.

Weather Services International (WSI), a member of The Weather Channel companies, also is predicting a colder than average winter 2011-12 for Ireland.

According to the UKMO’s John Hirst: “These stories do reflect our national obsession with the weather but they can also confuse and even scare vulnerable people. The Met Office’s job is to provide accurate and reliable information and at this stage we see no scientific evidence to support these premature predictions.”

“In fact the scientific capability does not exist to allow such extremes to be identified on a long-range timescale… no forecaster can say whether we’ll see a week of -20C temperatures in Manchester in the second week of December. This does not mean that harsh winter conditions are not possible, just that they cannot be identified at the moment.”

He continues: “As winter approaches, local government and businesses are preparing for the worst that the British weather can throw at us. But the fact that local authorities are stocking up on grit is no cause for alarm. This is what contingency planners do. In fact, their preparations are encouraging because they mean the country should be in a good position to respond to our short-range forecasts of severe weather.”

“Last year there was some confusion between our longer-range outlook which provided good advice over the whole winter – as January and February were relatively mild – and our shorter-range forecasts that correctly identified the prolonged cold and snowy weather early in the winter. In fact, our forecasts of where and when it would snow were second to none. Although it is not possible to prevent disruption, our detailed forecasts allowed agencies to put their resources in the right place at the right time to ensure that it was kept to a minimum.”

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Decided to post in here aswell but feel its needed in the other thread too to make it more positive

:)

December = CET -0.7C Extreme Cold

Very Below Average Precipitation

January = 0.7C Very Cold

Below Average Precipitation

February = 2.2C Cold but getting warmer

Just Below Average Precipitation

Published 16th October 2011

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Decided to post in here aswell but feel its needed in the other thread too to make it more positive

:)

December = CET -0.7C Extreme Cold

Very Below Average Precipitation

January = 0.7C Very Cold

Below Average Precipitation

February = 2.2C Cold but getting warmer

Just Below Average Precipitation

Published 16th October 2011

Nice forecast for we snow lovers but based on what?

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The quote above from Ray Anthony is very confusing - and again the language is terrible, absolutely terrible. All he needs to say is in his opinion the winter will make for much less headlines - than last winter. The bit about there may even be some flooding - yes most winters do see some flooding in some parts of the country - flooding occurs in summer as well. What point is he trying to make.

I am ignoring any forecast, predictions, anything associated with PWS.

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In essence drier than average for most of the UK, mildest in the NW, coldest in the SE. Looking farther afield,

dry and warm Iberia, dry W Europe, colder from Poland-Italy eastwards, coldest against the average in SE Europe

where there will be some significant snowfalls.. .as ever tho, time will tell.

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The quote above from Ray Anthony is very confusing - and again the language is terrible, absolutely terrible. All he needs to say is in his opinion the winter will make for much less headlines - than last winter. The bit about there may even be some flooding - yes most winters do see some flooding in some parts of the country - flooding occurs in summer as well. What point is he trying to make.

I am ignoring any forecast, predictions, anything associated with PWS.

Have to agree with this. Not sure if it's a direct quote, but if so it's gramatically shocking and leaves me with little confidence in it's conclusions... whatever they actually are!

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Don't think anyone's posted the WSI forecast, essentially it's the exact opposite of Accuweather regarding severity in particular areas. So, if they can't agree on anything then what chance have we mere mortals got?!

http://wsi.com/e7bd2...ase-details.htm

WSI (Weather Services International) expects temperatures for the upcoming period (November-January) to average lower than normal across the UK and western mainland with above-normal temperatures common across the eastern mainland, Southeast Europe and most of the Nordic region.

There are numerous indications that the cold will not be as extreme as it was during the last two winters,” said WSI Chief Meteorologist Dr. Todd Crawford. “The current state of the Northern Hemispheric oceans is almost identical to that observed in October 2008, which was only a moderately cold winter. Further, we have finally emerged from the unusually long lull in solar activity that likely contributed to the extreme nature of recent winters. Lastly, the multi-year tendency towards North Atlantic atmospheric blocking has already waned a bit in 2011, relative to the previous three years. This indicates that the atmosphere is likely regressing back to the mean a bit from the recent and persistent anomalous state. So, while we do expect another cold winter across UK and Western Europe, we think that the winter will be much closer to 2008-09 than 2010-11. Further, we think that the worst of the cold across Western Europe will be in December and January, and that the back-half of winter could be significantly milder.”

In November, WSI sees the monthly breakdown as:

Nordic Region* – Warmer than normal

UK * – Colder than normal

Northern Mainland* – Warmer than normal, except western France

Southern Mainland *– Warmer than normal

In December, WSI forecasts:

Nordic Region – Warmer than normal

UK – Colder than normal

Northern Mainland – Warmer than normal east, colder than normal west

Southern Mainland – Warmer than normal east, colder than normal west

In January, WSI forecasts:

Nordic Region – Warmer than normal

UK – Colder than normal

Northern Mainland – Colder than normal

Southern Mainland – Colder than normal, except southeastern Europe and southern Iberia

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Not exactly bringing "detail" and "depth" to the party with that forecast :)

I agree to a certain extent on their thoughts for the UK.

What sort of pattern do we think they are thinking will occur? Scandi High, Scandi Trough etc??

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A similar pattern to recent winters basically - cold in the west, warm in the east. Probably low heights over Scandi, a southerly jet and a strong Greenie high. I disagree with them.

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A similar pattern to recent winters basically - cold in the west, warm in the east. Probably low heights over Scandi, a southerly jet and a strong Greenie high. I disagree with them.

I actually agree with them lol :p as were already seeing in far reaches of FI the jet trying to dive south which is what I anticipate which was one of the things I included in my prediction :)

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It's always far easier to see what you want to see, rather than what you don't want to see - it's just human nature.

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Just a post here to let people know that i will be releasing a detailed winter forecast in late November. I am currently collecting data and analyzing it and then creating statistical models in order to attempt to get a grip on where winter will head.

It will be primarily a statistical and teleconnection based forecast with secondary factors being solar and sea surface temperature anomaly.

I need to wait until late November for all the October data to be out so that i can compare this to the models i am currently creating.

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OK here goes nothing .. :-)

December : Likely to be a continuation of drought for Southern and Eastern Areas, cold (but not excessivly so) by day, and where winds fall light under High Pressure plenty of frosts.

Always wetter in the NW of the UK, and some North Westerly's from time to time clipping Scotland giving plenty more mountain and hilltop snow, a mixture of wintery showers further south as occasional and temporary northerly incursions move south over NE England.

Midlands likely to see the best of any sunshine , a lot of mist and fog along Southern and some Eastern coasts.

A generally windy theme for Ireland and the NW.

I still think that things will change sometime around 20th Dec, the feed of weather to become increasingly Northerly, although Im not so sure how long this will last, it could well be that the winds and weather direction swing to a more North Easterly, and if this happens the East, North East, South East, and Scotland could well see a White x-mas, the west closer to High Pressure, and here we could see a battleground scenario take place.

If High Pressue holds firm, this could last until the beginning of Jan, but I think it's more likely that well see the blocking pattern move and end up more to the South of the UK, allowing the atlantic to slip through once again.

Jan I think we'll see a gradual increase in temperatures as we go through January, and a very mixed month to follow.

Lots of rain, strong winds, but also plenty of sunshine around, and some bright crisp days, High Pressure shifting around to be centered over the UK at times, Low Pressure feeding in from the North at times, to give more mountain snow, and snow over the hills of Northern England, Wales, and also parts of Ireland, but weather also encroaching from the South West at times, raising temperatures ntionwide as it does so

No real dominating pattern, so any blocking is likely to be temporary, resulting in a few cold days, perhaps a couple of snowy days almost anywhere, but I dont see there being day after day of cold.

Winds generally quite strong and when the feed is from the North, temporary blizzard conditions likely in Scotland.

FEB I Think Feb is likely to start off quite settled, but I believe that the UK is going to find itself sandwiched between 2 large High Pressure systems.

One over scandi, and one over Iceland, the result is the direcion of our weather from an etremely cold north, a true blast of winter finally comes, and as fronts move south, they drag in more North Easterly winds, and blanket much of the UK in snow, I think there will be a series of fronts passing from the NE of the UK, moving SE and we'll have a very cold first 2 weeks of Feb.

Generally overcast, winds brisk, but not extremely so, and temperatures very cold, lots of ice.

Just before mid Feb, things start to warm up, and a gradual increase in temperatures, winds fall light, and a slow thaw of any lying snow.

We might see a very stormy and wet end to Feb.

TO summarize :

Dec : Dry, perhaps colder than the average, windy, perhaps a widespread white chritmas (0.5 Degrees BELOW THE AVERAGE FOR CET)

Jan : Mixed month with no real dominating pattern ( AVERAGE CET)

Feb : Very cold forst half, warming up to end on a stormy note. ( 0.5 DEGREES BELOW THE AVERAGE FOR CET, a cold first half offset by a milder 2nd half)

That's my analysis, based upon the possible over cooking of La Nina (I believe we'll be at about negative 1 by Jan)..which is a weak La Nina, and not at negative 2 which is a moderate to strong La Nina, as is being forecast by CFS charts.

Sunspot activiy, although has increased, I believe there is a lag time in for the effects of increased activity to take effect on the large scale, I still think we'll experience a generally colder winter this time around, due to last years very quiet sun.

Jet Stream, it could well be the Jet stream that is the undoing of my forecast, it has movd much further north (as an average position) over recent months, my forecast is for this to be a teemporary blip, my forecast is for the jet to slip further south (as an average position) from end of Nov onwards

QBO AND NAO Im still not clued up about these really, so those are 2 things i'll be looking at and learning more about in 2012.

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AWT FINAL WINTER FORECAST PREVIEW

Winter 2011/2012

Factors Involved:

  • Recent, Low Solar Activity
  • La Nina and a predicted strengthening La Nina
  • The consitency of High Pressure over Greenland
  • Current and near future positioning of the jet stream
  • The Weather of the past 12 or so months

Overview

Essentially, I am predicting yet another below average winter for 2011/2012 with a wide variety of weather types and set ups. I am not expecting a winter that rivals the likes of 1962/1963 or 1946/1947, however I do expect this winter to carry on the theme of the past three winters with at least one notable and significant cold spell. The duration could be just a week or an entire month and the intensity could be very little snow with temperatures widely at 1c at day and -4c at night for a sustained period to a record breaking cold spell with large snow amounts and bitterly cold temperatures. However the entire winter will not be widely below average as I do expect more average and above average periods within the winter aswell as periods of average, settled conditions to unsettled polar martime air masses inbetween depressions. Short-lived and less intense cold spells are also expected this winter.

The reason for my forecast is the prominence and consistency of the Greenland High, which has been responsibe for cold spells during the past few winters and has been a notable factor in our weather for the past 12 months. With La Nina strengthening, I expect Febuary to be least likely month to see the worst of the winter weather - however it could pull out a surprise and bring a sharp and notable cold spell out of nothing. Unlike last year, I expect the winter to also be more balanced and we shouldn't see the same deprivation of snow that we saw in January and Febuary earlier this year - therefore I even expect Febuary (what is likely to be the milder month of the winter) to see at least some snow and cold.

The timing of events is uncertain, however with the Atlantic set to become a major feature during the end of October and most likely the majority of November (a simular output to 2010 and 2009), I expect this to be a catalyst for the weather this winter with most of the Atlantic activity to be done and dealt with before the winter comes. As we all know, a big freeze can come soon after an active period for the Atlantic. However I don't expect any significant cold spell to arrive immediatley after an active jet stream, instead I think any freeze up will happen at a time frame of at least 7 days after frontal activity stops or slows down. Therefore, I don't expect a significant big freeze this November as I expect most of the month to be dominated by the jet stream, however I can' rule out a short-lived cold spell during the second half of the month. If the Atlantic loses it's dominance in our weather by the end of November, I expect a severe cold spell to start at anytime between the 5th of December and the 20th of January (therefore I expect the most likely period for a major cold spell is December and/or January). At the moment I would say it's most likely that Northern Blocking will re-appear once more sometime in December with a cold spell lasting perhaps lasting into January depending on the duration and the beggining of the freeze. However if we are only restricted to polar maritime air masses between fronts aswell as short lived cold spells in December, I also expect January to be almost as reliable as December for a significant cold spell (perhaps we could end up with two spells of notable winter weather, however at the moment I would say that is quite unlikely). The period inbetween or before/after cold spell(s) should consist of anticyclonic conditions, an active jet, short lived cold spells. Febuary should be a month that sees some short lived cold spell during the first half of the month although you can't rule out a more significant blast of winter weather during the month - anyway, I expect Febuary to be more likely than November to face the highlight of the winter.

ROUND UP

DECEMBER 2011: Coldest Month of the winter with a significant period of cold and snowy weather developing sometime during the month, perhaps following a chilly period of atlantic fronts dragging cold polar maritime airstreams in behind aswell as the potential for some high pressure situated near or over the UK.

Mean Temp - Coldest (-1C), Warmest (3.5C), Likely (1.5C)

JANUARY 2012: Most likely to be the second coldest month of the winter with a significant chance of a big freeze if December fails to materialize. The month could comprise of the entire main cold spell happening within the month, or for a signifcant cold spell from late December into January/ January into Febuary. The month should also experience some Atlantic activity aswell as the potential for high pressure to rise in the east or even over the UK. The fluctuation and movement of the jet stream should also allow for some colder interludes from the Artirc.

Mean Temp - Coldest (-1.2C), Warmest (3.8C), Likely (2.1C)

FEBUARY 2012: Most unlikely to be the coldest month of the winter, however I do have some thoughts about a potential easterly. Therefore there is certainly some potential for my predicted major cold spell to happen in Febuary. Otherwise, I expect Febuary to overall be slightly milder with an active jet with some colder activity at times with the potential for frost and some snow in the north aswell as some nice settled spring like conidtions towards the end of the month.

Mean Temp - Coldest (0.7C), Warmest (6.4C), Likely (3.3C)

AVERAGE TEMPERATURE OVERALL: Likely (2.2C)

Chance of Big Freeze

START TIME FOR BIG FREEZE CHANCES:

November 1-15 - 5%

November 15-30 - 12.5%

December 1-15 - 25%

December 15-31 - 36%

January 1-15 - 33%

January 15-30 - 20%

Febuary 1-15 - 15%

Febuary 15-28 - 10%

Most Likely Period for a Big Freeze is between 10th December and 20th January.

My Predicted Big Freeze would be: December 20th - January 5th though anytime between December 5th and January 25th could see a big freeze and even Febuary could see something significant.

My more detailed analysis of each month of the winter shall be done soon although my hypothesis and prediction is already done.

AWT

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Cheers for this Reef. Only just seen this :)

I may update my forecast to tidy it up slightly soon.

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AWT FINAL WINTER FORECAST PREVIEW

Winter 2011/2012

Factors Involved:

  • Recent, Low Solar Activity
  • La Nina and a predicted strengthening La Nina
  • The consitency of High Pressure over Greenland
  • Current and near future positioning of the jet stream
  • The Weather of the past 12 or so months

Overview

Essentially, I am predicting yet another below average winter for 2011/2012 with a wide variety of weather types and set ups. I am not expecting a winter that rivals the likes of 1962/1963 or 1946/1947, however I do expect this winter to carry on the theme of the past three winters with at least one notable and significant cold spell. The duration could be just a week or an entire month and the intensity could be very little snow with temperatures widely at 1c at day and -4c at night for a sustained period to a record breaking cold spell with large snow amounts and bitterly cold temperatures. However the entire winter will not be widely below average as I do expect more average and above average periods within the winter aswell as periods of average, settled conditions to unsettled polar martime air masses inbetween depressions. Short-lived and less intense cold spells are also expected this winter.

The reason for my forecast is the prominence and consistency of the Greenland High, which has been responsibe for cold spells during the past few winters and has been a notable factor in our weather for the past 12 months. With La Nina strengthening, I expect Febuary to be least likely month to see the worst of the winter weather - however it could pull out a surprise and bring a sharp and notable cold spell out of nothing. Unlike last year, I expect the winter to also be more balanced and we shouldn't see the same deprivation of snow that we saw in January and Febuary earlier this year - therefore I even expect Febuary (what is likely to be the milder month of the winter) to see at least some snow and cold.

The timing of events is uncertain, however with the Atlantic set to become a major feature during the end of October and most likely the majority of November (a simular output to 2010 and 2009), I expect this to be a catalyst for the weather this winter with most of the Atlantic activity to be done and dealt with before the winter comes. As we all know, a big freeze can come soon after an active period for the Atlantic. However I don't expect any significant cold spell to arrive immediatley after an active jet stream, instead I think any freeze up will happen at a time frame of at least 7 days after frontal activity stops or slows down. Therefore, I don't expect a significant big freeze this November as I expect most of the month to be dominated by the jet stream, however I can' rule out a short-lived cold spell during the second half of the month. If the Atlantic loses it's dominance in our weather by the end of November, I expect a severe cold spell to start at anytime between the 5th of December and the 20th of January (therefore I expect the most likely period for a major cold spell is December and/or January). At the moment I would say it's most likely that Northern Blocking will re-appear once more sometime in December with a cold spell lasting perhaps lasting into January depending on the duration and the beggining of the freeze. However if we are only restricted to polar maritime air masses between fronts aswell as short lived cold spells in December, I also expect January to be almost as reliable as December for a significant cold spell (perhaps we could end up with two spells of notable winter weather, however at the moment I would say that is quite unlikely). The period inbetween or before/after cold spell(s) should consist of anticyclonic conditions, an active jet, short lived cold spells. Febuary should be a month that sees some short lived cold spell during the first half of the month although you can't rule out a more significant blast of winter weather during the month - anyway, I expect Febuary to be more likely than November to face the highlight of the winter.

ROUND UP

DECEMBER 2011: Coldest Month of the winter with a significant period of cold and snowy weather developing sometime during the month, perhaps following a chilly period of atlantic fronts dragging cold polar maritime airstreams in behind aswell as the potential for some high pressure situated near or over the UK.

Mean Temp - Coldest (-1C), Warmest (3.5C), Likely (1.5C)

JANUARY 2012: Most likely to be the second coldest month of the winter with a significant chance of a big freeze if December fails to materialize. The month could comprise of the entire main cold spell happening within the month, or for a signifcant cold spell from late December into January/ January into Febuary. The month should also experience some Atlantic activity aswell as the potential for high pressure to rise in the east or even over the UK. The fluctuation and movement of the jet stream should also allow for some colder interludes from the Artirc.

Mean Temp - Coldest (-1.2C), Warmest (3.8C), Likely (2.1C)

FEBUARY 2012: Most unlikely to be the coldest month of the winter, however I do have some thoughts about a potential easterly. Therefore there is certainly some potential for my predicted major cold spell to happen in Febuary. Otherwise, I expect Febuary to overall be slightly milder with an active jet with some colder activity at times with the potential for frost and some snow in the north aswell as some nice settled spring like conidtions towards the end of the month.

Mean Temp - Coldest (0.7C), Warmest (6.4C), Likely (3.3C)

AVERAGE TEMPERATURE OVERALL: Likely (2.2C)

Chance of Big Freeze

START TIME FOR BIG FREEZE CHANCES:

November 1-15 - 5%

November 15-30 - 12.5%

December 1-15 - 25%

December 15-31 - 36%

January 1-15 - 33%

January 15-30 - 20%

Febuary 1-15 - 15%

Febuary 15-28 - 10%

Most Likely Period for a Big Freeze is between 10th December and 20th January.

My Predicted Big Freeze would be: December 20th - January 5th though anytime between December 5th and January 25th could see a big freeze and even Febuary could see something significant.

My more detailed analysis of each month of the winter shall be done soon although my hypothesis and prediction is already done.

AWT

That would be a very cold winter.

Looking a bit of a long shot the way things are currently developng.

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Very much of a dreamcast but everything is a guess right now AWT. What do you classify a big freeze is though? And that would be our coldest winter in 49 years wouldn't it? I'd say it's quite unlikely; but it's all guesswork as I've said. Good luck awt!

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Very much of a dreamcast but everything is a guess right now AWT. What do you classify a big freeze is though? And that would be our coldest winter in 49 years wouldn't it? I'd say it's quite unlikely; but it's all guesswork as I've said. Good luck awt!

Well those mean temperature values take into account of the uncertainty I have with the timing of Northern Blocking. December's mean temp takes into account that a severe cold spell is possible and the same goes for January and Febuary is also uncertain about a cold snap in January into Febuary.

Realisticly, I think we will have one significant cold spell this year (i.e a Feb 2009 or a Dec 2010) and I believe it's most likely to happen in either December or January. At the moment I'm working on my complete final winter forecast with more precise detail. If you're wanting a hint about my feelings towards some sort of Big Freeze this year would be a start of 21st December and an end of January 4th.

My initial mean temp values took into count the uncertainty I had about timing and chance but if we take into count the cold spell that I have predicted in late December/early January then the temperature values should be: December 1.9c; January 2.4c; Febuary 4.4C.

In the coming days I will officially release my winter forecast and it should see a bit of a downgrade on the overall winter CET.

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Just remember November 2009 which was unsettled and very mild in my opinion, and then look what happened end of december and beggining of January, just becasue we might not get as much cold this november, doesn't December, January and February could be cold.

In my opinion I am going for a cold end of December and a cold and snowy January :)

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Just remember November 2009 which was unsettled and very mild in my opinion, and then look what happened end of december and beggining of January, just becasue we might not get as much cold this november, doesn't December, January and February could be cold.

In my opinion I am going for a cold end of December and a cold and snowy January smile.png

Yes things can change very quickly. I remember December 2000 which saw a great cold spell at the end of the month, however before Christmas, that December was incredibly mild. Even if we don't get a repeat of December 2010 or 2009/2010, as long as we have at least 15-20 snowfalls and 5-10 lying days with a white christmas and I'll be happy. A mild winter can also bring up some massive battleground snowfalls aswell.

With most of the atlantic activity in November, I feel quite optimistic about the winter. Remember the first signs of the earliest widespread snowfall in the UK for years was the 9th of November so we've got a long, long way to go.

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Remember the first signs of the earliest widespread snowfall in the UK for years was the 9th of November so we've got a long, long way to go.

The very first signs for an early cold and snowy start to Winter were actually picked up on in September 2010.

Obviously the fine detail wasn't nailed on but the overall signal was firmly in place well over 2 months in advance of the forthcoming winter.

So far the outlook for early winter 2011 is grim, which is fine as this could mean we are heading for a more traditonal UK Winter with cold arriving later in December and much more prominent cold conditions come Jan/Feb.

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