Winter Lrf By Rjs And Bftp

[BLAST FROM THE PAST]

Folks

I have had it in my possession since beginning of November, but held onto it to see how Nov Developed. The storm potential has made me think and I want to confer with Roger prior to final release. The New Moon/Full Moon perigee/apogee signal seems that it will be impressive come mid winter so 'potential' adjustments. No chnage from overall but maybe some tweaking. The storm potential for Nov has been realised on my side of forecast so need to speak to Roger.

Not to sound too cagey but JANUARY is the month and if one thinks of analogues then think when January was the month??!!.

BFTP

[Gavin P]

And.....

[Shiny_Bottom_1]

1947? The year my old man was born.

Looking forward to the forecast!

[geoffw]

so wheres the forecast bftp? you promised us all it would be posted today

[johnholmes]

1947? The year my old man was born.

Looking forward to the forecast!

nope-that January the real cold only started part way through the month

the coldest by some way-January is 1963 with a CET of -2.1C with the next at 1940 with -1.4C

[Roger J Smith]

I think it will be posted any moment now, Fred just wanted to see if I had any last-minute changes to suggest, more or less not from my recent re-reading of the draft ... but add details you feel are not in that draft, I agree with your comments in the PM about specific events down the road ... so post away old chum and may the force be with us.

Not the police force either.

By the way, here's a rough summary of my North American forecasts already in print on Easternuswx.com and other places too ...

For the eastern and central regions, very mild weather that developed since October 20th is likely to continue until about mid-December with a few brief interruptions, and there could be a few more near-record highs especially in the period 2-5 December.

Later in December, a colder regime will gradually develop as a trough is carved out on the east coast. The western regions will stay mild, relatively dry in the usually rainy Pac NW and BC, relatively wet in CA especially central and southern.

January may be one for the ages with cold and snow in abundance in the east. The west will remain in the same mild pattern with more heavy rains in the Los Angeles region leading to flooding and mudslides. It may be an active severe weather month in Texas and Louisiana. The month will perhaps end with intense storms on the east coast as the flow begins to buckle sharply in response to retrogression across the Canadian arctic.

February may turn much milder and melt the snow in the northeast US and Great Lakes basin, due to rain and thaw combinations, and this could become excessive in some parts. Temperatures will reverse from much below normal in January to much above in February. Western regions will continue rather mild and our Winter Olympics may come under some stress at least for the lower alpine sites near the city of Vancouver; the higher alpine sites and of course all indoor sites will be fine, but we have some ski hills being used for X-C and ski jumping events that are prone to total meltdowns in mild winters.

The early spring will continue warm.

I assess the El Nino as moderate and west-based but likely to flare at times into marginal strong and central-based, so it could be rather like 1982-83 for some effects, but with better mixing in of arctic cold especially east of 100W. How this all feeds into the European winter forecast will be evident when Fred posts our thoughts on that.

Can say that forecast is on track because as you'll see in the CET section I went for 8.5 C which seems pretty close to the eventual landing point for November.

In general terms I think the westerly index will be quite high this winter, and any attempts to set up blocking or retrograde patterns will only succeed briefly if perhaps rather spectacularly in one or two cases -- the retrograde sub-index is highest from mid-December to mid-January in our research for this season.

Edited November 17, 2009 by Roger J Smith

[Gavin P]

I'll say January 1940.

[mcweather]

I,ll say January 1963 just for fun

[Gavin P]

Roger, before your winter forecast is posted, I wonder if you've got any views through your research about what happens with ENSO through 2010? I've seen some posts in easternweather saying that El Nino will never really go away next year and might even stregnthen to become a "mega event" later in the year!

IS that something you'd go along with? Or do you think we'll see the traditional winter peak of this current El Nino followed by a classic switch to neutral or even La Nina through spring and summer?

Edited November 17, 2009 by Gavin P

[Roger J Smith]

Gavin, my research index model for the El Nino showed it peaking this coming winter and then backing off to neutral around 2011, swelling back to moderate or even strong in 2012.

I don't issue any guarantees with that, it's just the one research tool that I have from my perspective, otherwise I tend to accept whatever the more familiar ENSO specialists have to say about it.

Listen, if Fred doesn't happen to post the forecast by say 11 pm, I will post my draft and he can always add some other thoughts tomorrow, we have already discussed the basic concepts and there was just a bit of concern about one set of events that I would need to rewrite perhaps one or two sentences briefly.

[Gavin P]

Thanks Roger.

It'll be quite a novelty to get an ENSO neutral winter for 2010/2011, so I hope your right.

[Snow Queen one]

Thanks Roger.

It'll be quite a novelty to get an ENSO neutral winter for 2010/2011, so I hope your right.

What does this mean please?

[Gavin P]

It just means that we are not in an El Nino or La Nina phase and central Pacific temps are normal.

[Roger J Smith]

Alright then, here's the updated version of our winter forecast for 2009-10 ... lots of variety, a stormy theme, January to be the best month for potential cold or snow.

RJS + BFTP Winter Forecast 2009-10

______________________________________

Once again, our winter forecast will be based on a consideration of research model output (in the form of selected index values for historical analogues) and the large-scale global and hemispheric factors that influence all long-range forecasts to some extent.

First of all, there seems to be a good chance of a persistent moderate El Nino which we take into account mainly as a likely background source for stronger energy levels in the western Atlantic. This would tend to show up in our blended technique as insertion of milder air into higher-latitude lows leaving eastern North America, so at times when other index values indicate mild potential, it could then become very mild.

At the same time, the El Nino is competing with a persistent trend of strong arctic outflow in central North America which may at times keep the milder circulation locked into the southwestern parts of North America and set up ideal downstream conditions for blocking and cold air development over Europe.

SST values across the North Atlantic are rather warm at present and this favours both a milder winter regime and more energetic storms.

The lunar-geomagnetic research variables show a tendency towards a monthly cycle for the winter period that peaks in temperature a few days after each full moon, and falls off sharply to a minimum after each new moon event. This seems especially strong in the January analogues we studied.

The storm track energy cycle has a pronounced 7-day modulation this winter due to secondary peaks happening to fall just about midway from "northern max" (which is at full moon in early winter) and "southern max" (at new moon). So this tends to set up the possibility of longer spells of dry weather with stronger storms, rather than a pattern of never-ending two to three day cycles of lows, ridges and more fronts and lows moving through.

Taking all this as guidance, and accepting that this is not a winter where we feel we have a clear signal of any overall trend, we are saying the following in our forecast.

(this part is old news now, but this was the original draft with a couple of added notes today) ... NOVEMBER is likely to continue unsettled much of the time, with a rather mild overall tendency, which may be more pronounced towards the end of the month. (I could note that I said this in October but Fred wanted to see how this recent energy peak played out in reality, in case we went into a blocking pattern before the main part of winter arrived -- it would continue to appear that the Atlantic will rage on and off for several more weeks yet) ... We expect it to be a rather windy month and near normal in rainfall (it's turning out quite wet towards the west and in Ireland, and I haven't seen any reports of snow yet except on higher hills).

WINTER FORECAST

__________________

DECEMBER is probably going to start off very mild, with possible near-record temperatures generally close to the northern max after the 2 Dec full moon (4-5, 7-8 Dec should see peaks) and this may be a fairly long mild spell that if not too windy at first (and it may be in the north especially) should evolve into a stormy pattern mid-month, before turning much colder in the days before Christmas. Retrograde or blocking index will rise sharply in mid-December which could be a signal for an inversion high to develop at or after the mid-month new moon; there could also be a strong southward diving episode setting up a more wintry pattern just before Christmas. If the new moon event (15-16th) is not blocked out and sent up towards Greenland, then it might well be a strong wind event in Britain. There would seem to be a chance of a white Christmas because the coldest part of the month from index values is the 23rd to 27th. That will depend on whether there is a strong inversion high or a less blocked cold pattern at that point. The end of the month would then be expected to turn much milder again with potential for a big rain and wind storm right around New Years Eve, with the near-perigeean full moon (coincident with northern max at that time) at 1914h GMT on 31 Dec. Watch for a sort of double-centered powerhouse low to come barrelling in from around the central Atlantic across northern parts of the British Isles with this energy peak. This would be an event that could feature damaging winds and exceptional tides or even a storm surge somewhere in the south or west coastal regions.

JANUARY looks like it could be the best winter month. The early mild spell should begin to shift as colder air builds up over Scandinavia and Iceland. We foresee some chance of a wintry spell in the UK from about the 5th onward, with some chance of snow cover being established for a week or two, and a storm opportunity around the 14th-15th that could be a snowstorm (more likely cold rain in the southwest). If indeed the winter turns into a stormy one, this mid-January low could be quite intense. If it is blander in general, this would be a moderately strong event probably. Further snow could develop at times before an end of the month warming trend and, with a perigeean full moon on the 30th, we have to be alert for another possible major wind storm developing in the period 29th-31st. Major wind storms have occurred in the past in roughly similar high-westerly-index winters with a late January full moon, for example in 1953 and 1983.

FEBRUARY could be milder than normal as the developing winter El Nino pattern begins to release a lot of storm energy from the southeast U.S. towards the central Atlantic. The index for retrograde motion peaks in mid-January from our research, which often means that a secondary block of a southerly nature will develop over Europe as the main retrograde signal moves west to Baffin Island or Hudson Bay. As a result, we would not be surprised if February turned more spring-like and came in above normal in temperature.

A rough estimate of CET values for the three months would be 5, 3, 5. Once again, January has some potential to go even lower than 3, we said this last winter and I think it hit right on 3.0 ... but after quite a cold first ten days ... and last winter, while this doesn't count towards forecast verification it's interesting to note that the coldest 30 days of the winter season averaged fairly close to zero C. So we can safely say that the atmosphere can now sustain old-fashioned cold and snow for at least significant periods, if not up to the standards of perhaps the 1940s or such winters as 1963 and 1986. There remains the outside chance that this winter could go into some sort of exceptional blocking pattern after mid-December and produce something really sustained and memorable ... not any indication strong enough that Fred or I have a very strong feeling about that, but I don't think either of us would be amazed if this winter became a "big one" somehow, for one thing, we have to keep in the back of our minds the long interval of quiet solar activity with its partly unknown connections to the weather parameters such as the intensity of the arctic vortex or the background true level of the temperature trend lines from which the anomalies will actually develop in practice.

On the other hand, I have to be absolutely honest here and say that a sort of 2006-07 mostly mild with one or two late redeeming snowfalls scenario is not off the table either; once the Atlantic starts to roar, it's sometimes hard for retrogression or blocking to slow it down altogether. The one thing about this winter that's different from 2006-07 in that regard, is that the retrograde signal is both earlier and oriented a bit further south, in my research (peaking early January as opposed to mid-late February in that case) ... a good way to visualize this coming winter might be to imagine the winter of 2006-07 all coming about a month to six weeks earlier and you can see where we are at now in that comparison.

By the way, the indications continue on to show a mild or even warm March.

Lots to chew on there, and we'll be happy to add more details from our perspective if we have them available this week or next while this is still a forecast and not a nowcast situation ... and we'll also be glad to field your questions but to forestall inevitable repeats of other years, our methodology is based on extensive numerical cycle analysis of what we believe to be suitable analogue sets of data, and yes there are other approaches, we don't look down on them, we sometimes wonder if they reflect a different way of doing the same calculations so to speak ... and when I have spare time, I even try to research that question too. At some point, you just have to go with what you've got in your own arsenal and let the chips fall where they may. I think our techniques are improving over time, shall we say, and obviously there is always lots of room for improvements too, this is not being presented by any means as "finished science" but the ongoing results of a combined research and forecasting program.

I would buy wind insurance if I were you (and if you live in Cork, I would buy it today).

Edited November 17, 2009 by Roger J Smith

[LomondSnowstorm]

Very interesting forecast. Slightly different to what I'd imagined, not so much in terms of overall temperatures but in forecasting a mild February. Your forecast for last winter and this summer were pretty much on the mark so I wouldn't expect this forecast to be too far out. I wouldn't be too upset with the winter forecasted either, lots of interesting storms in between snowfall events! In terms of CETs it looks similar to 86/87 with a cold January but milder in December and February.

Best of Luck with the forecast

CW

[Gavin P]

Thanks Roger and Blast. A very interesting winter there.

[blitzen]

Not to sound too cagey but JANUARY is the month and if one thinks of analogues then think when January was the month??!!.

1984!

[MAF]

Thanks Roger and Fred, a very good read and lots of hope for a winter that is neither overly mild or too dry. lets hope your feelings for Jan '10 come to fruition and that we have a blast of winter that many of the younger members may have not seen before :lol:

[Charltonkerry]

Very interesting and easily understood. Thanks very much for both of yours tremendous effort and time, being an old git who can still remember the winter of 62/63 it is nice that you are not forcasting one of those, would be nice to get a prolong period of cold with occassional snow as the youngster have not experienced say 3 or 4 weeks this, going by your forecast (assuming i read it correctly) this could be a possibilty.

Thanks again

Kerry

Edited November 18, 2009 by Charltonkerry

[BLAST FROM THE PAST]

Alright then, here's the updated version of our winter forecast for 2009-10 ... lots of variety, a stormy theme, January to be the best month for potential cold or snow.

RJS + BFTP Winter Forecast 2009-10

______________________________________

Once again, our winter forecast will be based on a consideration of research model output (in the form of selected index values for historical analogues) and the large-scale global and hemispheric factors that influence all long-range forecasts to some extent.

First of all, there seems to be a good chance of a persistent moderate El Nino which we take into account mainly as a likely background source for stronger energy levels in the western Atlantic. This would tend to show up in our blended technique as insertion of milder air into higher-latitude lows leaving eastern North America, so at times when other index values indicate mild potential, it could then become very mild.

At the same time, the El Nino is competing with a persistent trend of strong arctic outflow in central North America which may at times keep the milder circulation locked into the southwestern parts of North America and set up ideal downstream conditions for blocking and cold air development over Europe.

SST values across the North Atlantic are rather warm at present and this favours both a milder winter regime and more energetic storms.

The lunar-geomagnetic research variables show a tendency towards a monthly cycle for the winter period that peaks in temperature a few days after each full moon, and falls off sharply to a minimum after each new moon event. This seems especially strong in the January analogues we studied.

The storm track energy cycle has a pronounced 7-day modulation this winter due to secondary peaks happening to fall just about midway from "northern max" (which is at full moon in early winter) and "southern max" (at new moon). So this tends to set up the possibility of longer spells of dry weather with stronger storms, rather than a pattern of never-ending two to three day cycles of lows, ridges and more fronts and lows moving through.

Taking all this as guidance, and accepting that this is not a winter where we feel we have a clear signal of any overall trend, we are saying the following in our forecast.

(this part is old news now, but this was the original draft with a couple of added notes today) ... NOVEMBER is likely to continue unsettled much of the time, with a rather mild overall tendency, which may be more pronounced towards the end of the month. (I could note that I said this in October but Fred wanted to see how this recent energy peak played out in reality, in case we went into a blocking pattern before the main part of winter arrived -- it would continue to appear that the Atlantic will rage on and off for several more weeks yet) ... We expect it to be a rather windy month and near normal in rainfall (it's turning out quite wet towards the west and in Ireland, and I haven't seen any reports of snow yet except on higher hills).

WINTER FORECAST

__________________

DECEMBER is probably going to start off very mild, with possible near-record temperatures generally close to the northern max after the 2 Dec full moon (4-5, 7-8 Dec should see peaks) and this may be a fairly long mild spell that if not too windy at first (and it may be in the north especially) should evolve into a stormy pattern mid-month, before turning much colder in the days before Christmas. Retrograde or blocking index will rise sharply in mid-December which could be a signal for an inversion high to develop at or after the mid-month new moon; there could also be a strong southward diving episode setting up a more wintry pattern just before Christmas. If the new moon event (15-16th) is not blocked out and sent up towards Greenland, then it might well be a strong wind event in Britain. There would seem to be a chance of a white Christmas because the coldest part of the month from index values is the 23rd to 27th. That will depend on whether there is a strong inversion high or a less blocked cold pattern at that point. The end of the month would then be expected to turn much milder again with potential for a big rain and wind storm right around New Years Eve, with the near-perigeean full moon (coincident with northern max at that time) at 1914h GMT on 31 Dec. Watch for a sort of double-centered powerhouse low to come barrelling in from around the central Atlantic across northern parts of the British Isles with this energy peak. This would be an event that could feature damaging winds and exceptional tides or even a storm surge somewhere in the south or west coastal regions.

JANUARY looks like it could be the best winter month. The early mild spell should begin to shift as colder air builds up over Scandinavia and Iceland. We foresee some chance of a wintry spell in the UK from about the 5th onward, with some chance of snow cover being established for a week or two, and a storm opportunity around the 14th-15th that could be a snowstorm (more likely cold rain in the southwest). If indeed the winter turns into a stormy one, this mid-January low could be quite intense. If it is blander in general, this would be a moderately strong event probably. Further snow could develop at times before an end of the month warming trend and, with a perigeean full moon on the 30th, we have to be alert for another possible major wind storm developing in the period 29th-31st. Major wind storms have occurred in the past in roughly similar high-westerly-index winters with a late January full moon, for example in 1953 and 1983.

FEBRUARY could be milder than normal as the developing winter El Nino pattern begins to release a lot of storm energy from the southeast U.S. towards the central Atlantic. The index for retrograde motion peaks in mid-January from our research, which often means that a secondary block of a southerly nature will develop over Europe as the main retrograde signal moves west to Baffin Island or Hudson Bay. As a result, we would not be surprised if February turned more spring-like and came in above normal in temperature.

A rough estimate of CET values for the three months would be 5, 3, 5. Once again, January has some potential to go even lower than 3, we said this last winter and I think it hit right on 3.0 ... but after quite a cold first ten days ... and last winter, while this doesn't count towards forecast verification it's interesting to note that the coldest 30 days of the winter season averaged fairly close to zero C. So we can safely say that the atmosphere can now sustain old-fashioned cold and snow for at least significant periods, if not up to the standards of perhaps the 1940s or such winters as 1963 and 1986. There remains the outside chance that this winter could go into some sort of exceptional blocking pattern after mid-December and produce something really sustained and memorable ... not any indication strong enough that Fred

or I have a very strong feeling about that, but I don't think either of us would be amazed if this winter became a "big one" somehow, for one thing, we have to keep in the back of our minds the long interval of quiet solar activity with its partly unknown connections to the weather parameters such as the intensity of the arctic vortex or the background true level of the temperature trend lines from which the anomalies will actually develop in practice.

On the other hand, I have to be absolutely honest here and say that a sort of 2006-07 mostly mild with one or two late redeeming snowfalls scenario is not off the table either; once the Atlantic starts to roar, it's sometimes hard for retrogression or blocking to slow it down altogether. The one thing about this winter that's different from 2006-07 in that regard, is that the retrograde signal is both earlier and oriented a bit further south, in my research (peaking early January as opposed to mid-late February in that case) ... a good way to visualize this coming winter might be to imagine the winter of 2006-07 all coming about a month to six weeks earlier and you can see where we are at now in that comparison.

By the way, the indications continue on to show a mild or even warm March.

Lots to chew on there, and we'll be happy to add more details from our perspective if we have them available this week or next while this is still a forecast and not a nowcast situation ... and we'll also be glad to field your questions but to forestall inevitable repeats of other years, our methodology is based on extensive numerical cycle analysis of what we believe to be suitable analogue sets of data, and yes there are other approaches, we don't look down on them, we sometimes wonder if they reflect a different way of doing the same calculations so to speak ... and when I have spare time, I even try to research that question too. At some point, you just have to go with what you've got in your own arsenal and let the chips fall where they may. I think our techniques are improving over time, shall we say, and obviously there is always lots of room for improvements too, this is not being presented by any means as "finished science" but the ongoing results of a combined research and forecasting program.

I would buy wind insurance if I were you (and if you live in Cork, I would buy it today).

Hi Folks

Sorry I have a 4 1/2 year old who has recovered from a flu and now my wife is laid up with it. I work a shift pattern yet I have to ensure my lad is taken care of etc etc etc.

The mention of 86/7 as analogue has been mentioned elsewhere and is one that I have looked at as being a good reference point. The cold regime will quickly develop and may appear to come from nowhere.

Dec 86 although mild did hint at the potential down the line. Roger has covered the point very well that there is potential for the cold pattern to embed itself and this is an area I have been looking at over previous couple of weeks but I think that a more extreme pattern in Jan is more likely than a very prolonged cold set up. It is the jet's positioning that is crucial here and I believe that January will be on the colder side of our thoughts and that also there is affirmation that the peak energy periods will be very stormy indeed [and will be direct hits rather than way to the north and clipping the UK]. I base this on the idea that Oct and particularly Nov have verified very well indeed and although the sun is in a minima deeper than 'most' expected it is very pro-actively interracting with our atmosphere. I believe that storm potential in Jan will be forced south or on a cold trajectory [NW/SE access and with Rogers research of retrograde....then ingredients are there for the 1-2 week very snowy and very cold spell. We are cautious because of the background warming that has been experienced but as Roger says big chunks of last winter proved that sustained cold is very much achievable.

Roger , thanks for posting it in my absence. Lots going on guys so I will be very infrequent on here for sometime.

regards

BFTP

[Fozfoster]

An interesting and well put together forecast. good luck guys.

[Richie V]

To be honest, I'm looking forward to the prospect of a stormy winter. The last few seem devoid of gales. A snowy spell would'nt go a miss too! :unsure:

[Coast]

Not to sound too cagey but JANUARY is the month and if one thinks of analogues then think when January was the month??!!.

OMG! :unsure: More suspense than an Alfred Hitchcock movie......

Thanks for the forecast guys, always interesting and it will be good to analyse it at the end of the season.

[Mark Bayley]

Interesting forecast, January would always be the month i would hope to be snowiest, equally I'm looking for a white Christmas. Your forecasts seems to suggest that both are possible As ever though long range forecasts must be taken with a pinch of salt, but good luck :)

[SteveB]

I like your methods for long range forcasting.

And although your going for some cold spells in January, over all it seems like and average winter your calling.