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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
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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.
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
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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.
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.
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.
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
Quote
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
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
Quote
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
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
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 
