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BLAST FROM THE PAST

Rjs And Bftp Winter 2010/11 Lrf

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Winter 2010/11 - Cold with spells of severe wintry blasts.

RJS theory needs no introduction, well known, well publicised on the forum. It is archived for all to read and digest.

I basemy calculations on the solar phases. We have entered the La Nina dominant perturbation cycle since 2007. This correlates very well with a -ve NAO base state and a southerly tracking jet. Both of these have been and are being observed since then. It is a main player in why 08/09 with no northern blocking still saw a cool winter because the jet tracked south, last winter despite El Nino we saw a different hemispheric reaction and why I think likewise this winter.

We both factor in the lunar phases with full moon, new moon, perigee and apogee having affects on LP and HP development.

WINTER 2010-11 FORECAST -- COLD WITH CONSIDERABLE SNOW POTENTIAL

_____________________________________________________________

We have looked at the results of research index calculations and conventional forecast indicators, and determined that the winter may bring a third consecutive below-normal trend in temperature, with considerable snowfall possible in the U.K. and Ireland.

The global climate trends of La Nina will likely create a strong and active jet stream, but we only see this making northward forays on brief occasions possibly separating the winter into two distinct cold periods with later January forming a brief milder interval.

A very important part of our forecast scenario as in previous winters is the timing of retrograde motion in Europe, which we believe will begin to develop earlier this winter than last, and possibly turn the weather quite cold even in late November.

DECEMBER - CET 2.8C

There are indications of a very cold December with possible heavy snowfall events in central and northeast England, but also some snow from cold northwest flow patterns. We're predicting a rather low CET value of 2.8 C for December and some stretches of sub-freezing temperatures, most likely in the middle third of the month.

Moderate to heavy snowfalls are possible during this cold spell and most likely dates for these would be around the 6th and 13th (although 2-4 day periods of snowfall are likely). The southwest may escape this phase of the cold to some extent and see chilly rainfalls at least near sea level. With this early snow cover coming before the longest nights of the season, there is some chance of some notably cold overnight lows developing as high pressure swells up over northern central Europe in the days before the full moon on the 21st. An important storm event is likely to accompany this full moon, and it may produce another snowfall at least away from the south coast as the track of the event based on past analogues may be near to the Channel. The storm is likely to approach from WSW and is likely to slide under the block to the NE. If the trend happens to be milder than we're using as our base-line, this storm would bring mild, windy and rainy conditions but current indications for those conditions seem destined more for France and perhaps the coastal parts of Devon and Cornwall.

Following this storm system Christmas is likely to be dominated by HP and calm, cold and potentially freezing fog conditions may be prevalent.

Pressure is always higher to northern quadrant and the general flow remains North of E and W[indeed the set uop projected by models currently is a very good indicator of pressure pattern]. Further snowy conditions are possible shortly afterwards say 28th (all these snowfall forecasts are based on energy level peaks which are expected to form a fairly regular 7-day pulse in mid-winter, evolving into a 3.5-day cycle by February as two separate chains of events with different timing separate out from each other). We should note also that the energy level peaks are very strong this winter, so that parts of Europe will be battered by very strong winds and heavy precipitation. In general, look for these events around the new and full moons for simplicity.

JANUARY CET 3.0C

During the first half of January this cold and wintry scenario is likely to continue through mid-month with further heavy snowfalls possible at times. There may also be some severe cold as Continental Arctic air is likely to be generally in control and calm periods between energy peaks could see very low temps over the snow fields. The January CET value may be sitting close to or below zero until milder air punches through later in the month. The block is likely to recede allowing a period of more zonal flow allowing milder air to flood through.

Once the block is broken down, it may flip over to near-record warmth for a few days around the January northern max and full moon period coming near the 17th to 20th. Here again, if our timing is off at all, that energy peak could produce another snowstorm, but our index values show a peak in temperatures at this time but of note from such a cold state the mildness may not be that stark. The period immediately before this milder turn could be somewhat similar to the snow to freezing rain to rain scenario of January 1982.

FEBRUARY - 2.0C

A second wave of arctic cold and blocking highs is considered quite likely for February, and the mild spell will probably fade out with some mixed precip storms as retrograde motion sees a Scandinavian high pressure reasserts itself which will link across to Greenland. As the month progresses HP retrogrades to Greenland and southern Scandinavia will be subject to troughing. We could foresee some very cold weather in February as a result of the renewed blocking as the strong initial easterly flow becomes a north and then NE'ly. We're speculating that a very low CET value could be observed in February, perhaps the lowest in recent years (we'll say 2.0 as a conservative estimate but would not be surprised by something quite lower) as to our east will be in the grips of a severe winter. We'll issue some more detailed predictions on snowfall dates in the second half of the winter if the pattern seems to be on course but a generally unstable airflow from over the North Sea is anticipated so periods of heavy snow likely.

March is likely to recover only slowly from this arctic trend and there may be more snow and frosts well into the month before a gradual recovery to more normal conditions.

The CET values are unlikely to be the story teller. Last winter is a classic example and so one asks not to be overly studious on these values.

RJS and BFTP

We are hopeful :)

---------------------------

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Yes per-lease! :D

Great read BFTP & Roger, let's hope you are right again!

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Thanks guys. :drinks:

If your correct this winter sounds comparable to the strong La Nina winter of 1917. :cold:

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There are indications of a very cold December with possible heavy snowfall events in central and northeast England

...and the rest of the UK?! :p

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WOW!! looks great, I too hope it comes true, we missed out big time in the snow department last winter here in the midlands and need to redress the balance. GJ :good:

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I'd like this to be right of course, but this is the best case scenario, which often doesn't pan out.

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I'd like this to be right of course, but this is the best case scenario, which often doesn't pan out.

A well needed reality check i think, still we can dream...

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Just looking at Mondy's question, the sort of pattern we're expecting should bring above normal snowfall just about everywhere but central and northeast England would stand out with the largest amounts. I would say that this pattern would be good for snowfall in eastern Scotland but this may not be an "easterly only" regime for snow and some cold north or northwest wind situations could bring snowfall to western districts of the U.K. at times.

Thanks to Fred for posting this and as you'll see "reading between the lines" there are indications (to us at least) of a fairly severe winter ahead. The arctic has looked fairly healthy from the start, and I've mentioned in some earlier posts that the good start to winter in central Siberia can only be a positive for a cold winter in the UK and Europe in general because that's your source region.

By the way, my personal LRF for North America calls for periods of extreme cold to be fairly frequent in a corridor from Alaska and Yukon southeast into the western Great Lakes region, sometimes extending into the northeast U.S., while the southeast U.S. tends towards a milder than average regime. This would certainly promote a deep vortex over Baffin Island that may at times suppress Greenland highs, but this is not inconsistent with a Scandinavia-Iceland sort of blocking high pattern that is somewhat further east than last winter's persistent Greenland-Baffin blocking highs.

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Great read and also being in central england makes it even better if it pans out thank you guys :drinks:

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Thank you Roger and Fred for the work you have put into this LRF. Fingers crossed you're close to the mark.

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Interesting read - supports many long range forecasts of a cold December. Would be nice to see cold conditions set in early in the season and hold right through till christmas and beyond, been a long time since this has happened not since 1996 (2008 saw a flip to very mild weather mid Dec, and last year the cold didn't start till middle of the month).

I'd much rather have a cold snowy first half to the winter than a cold snowy second half - its very difficult to see cold snowy conditions sustain through the first half, 1996/97 and 1981/82 (though we saw a mild spell around new year) being two good examples of this, but the last two years have seen a change in fortune for the first half of the winter it seems - a good cold snowy run up to christmas is what I always hope for..

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Well I certainly won't be too unhappy if this forecast comes off! Cheers guys

:D:cold:

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Winter 2010/11 - Cold with spells of severe wintry blasts.

That's a stonker boys.

I really hope it comes off ....... though already looking good !!

Y.S

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interesting indeed. and although LRF's are difficult to compose, if the indications are as you see them, then we can at least look forward to a "normal" winter and not a BBQ one :D

thank you for your effort and publication of your LRF guys :)

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Top work, guys. Hoping your forecast is right and that we see another memorable winter. If we do, dare we suggest a pattern change has occurred? :whistling:

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Great forecast, adds to the much excitement on here, mention snow and everyone goes wild, i really can feel the uplift on NW!

i dont think many are to be disapointed this winter at all. (:

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By the way, my personal LRF for North America calls for periods of extreme cold to be fairly frequent in a corridor from Alaska and Yukon southeast into the western Great Lakes region, sometimes extending into the northeast U.S., while the southeast U.S. tends towards a milder than average regime. This would certainly promote a deep vortex over Baffin Island that may at times suppress Greenland highs, but this is not inconsistent with a Scandinavia-Iceland sort of blocking high pattern that is somewhat further east than last winter's persistent Greenland-Baffin blocking highs.

Certainly seems to be the theme for the winter forecast over here..much colder than last year..already the cold is spilling out across the priaires highs of -8c tomorrow and highs of -18c by sunday.

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