Winter Lrf By Rjs And Bftp

[Snowyowl9]

Interesting forecast guys and after your forecast last winter which was very good indeed.

There are similarities with november 1986 so far,floods that november and december but the biggest november floods I can remember,no floods just yet but the way it`s going it`ll be heading that way.

A few charts from then.

http://www.wetterzentrale.de/archive/ra/1986/Rrea00119861128.gif

http://www.wetterzentrale.de/archive/ra/1986/Rrea00119861210.gif

http://www.wetterzentrale.de/archive/ra/1986/Rrea00119861218.gif

Edited November 18, 2009 by Snowyowl9

[BLAST FROM THE PAST]

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.

Hi Steve

Thanks, really we are maintaining caution with the forecast. Patterns can become stubborn to shift so there is an awareness of that in the forecast. Re January, there is a signal that suggests an 'extreme' cold event is very possible, but Uk suffers more near misses than hits. However, there does seem the tendency for the jet to stay a fair bit south compared to recent years [bar last two] and with the very stormy signal it could be bingo. We will try and updat as we go along if that seems more likely than not.

I feel compelled to break my sabbatical [ill family so manic etc] for a while because of recent events. The stormy and extremely wet weather is in timing with my Nov LRF notable events though the cold is staying away which was caveated. I want to mention the December periods coming up. The build up to the stormy midmonth pattern say 7th to 14th could well produce more gales and flood problems and indeed will cause flooding somewhere [prob northern England again] and the storm signal for New Year is very very strong and again needs to be watched with hawk eye....these periods are very concerning.

BFTP

Edited November 20, 2009 by BLAST FROM THE PAST

[Iceberg]

It's a bit of forecast to suit all people really, if its a generally mild winter it would be correct, if its a winter with some extreme cold it would be correct, ditto anything in between.

Interesting thoughts though.

[Roger J Smith]

We're honestly not trying to cover all bases, we have drawn the conclusion from the research that there will be a mixture of pattern types as suggested here, but we acknowledge uncertainty that could result in either mild or cold eventually winning out.

However, I would consider verification to be something close to the mixed bag predicted, and I promise we won't try to claim enormous accuracy if the winter runs very mild or very cold, or if the timing of a mixed bag is substantially different.

I do agree with Fred that there's a good indication of a major cold snap in January, most of the index values tend to fall to low temperature signals about mid-month.

I tend to trust the Netweather community as a whole, to give these things a fair and balanced assessment, and last winter I thought we had responses that were generally fair and balanced.

Do you want to see our e-mails? They are pretty bland stuff mostly.

[azores92]

hi, does anyone have the 08/09 forecast by rjs and bftp to hand? id be interested to see it to relive the memories and see its accuracy

azores

[SteveB]

Hi Steve

Thanks, really we are maintaining caution with the forecast. Patterns can become stubborn to shift so there is an awareness of that in the forecast. Re January, there is a signal that suggests an 'extreme' cold event is very possible, but Uk suffers more near misses than hits. However, there does seem the tendency for the jet to stay a fair bit south compared to recent years [bar last two] and with the very stormy signal it could be bingo. We will try and updat as we go along if that seems more likely than not.

I feel compelled to break my sabbatical [ill family so manic etc] for a while because of recent events. The stormy and extremely wet weather is in timing with my Nov LRF notable events though the cold is staying away which was caveated. I want to mention the December periods coming up. The build up to the stormy midmonth pattern say 7th to 14th could well produce more gales and flood problems and indeed will cause flooding somewhere [prob northern England again] and the storm signal for New Year is very very strong and again needs to be watched with hawk eye....these periods are very concerning.

BFTP

I think you hit the nail on the head re the comment regarding UK getting more near misses than hits.

Such a tiny Island, it really is only the mother load winter set-up that can guarantee the UK getting a true cold spell.

[shuggee]

hi, does anyone have the 08/09 forecast by rjs and bftp to hand? id be interested to see it to relive the memories and see its accuracy

azores

Posted a week earlier than this year's splendid contribution on 10 November 2008:

http://forum.netweat...y-rjs-and-bftp/

[azores92]

Posted a week earlier than this year's splendid contribution on 10 November 2008:

http://forum.netweat...y-rjs-and-bftp/

:lol:

thanks

[Solar Cycles]

Only just got round to viewing this forecast, due to the old laptop being repaired. Lot's to chew over, and there does seem a lot of uncertainty, with regards to all the mixed signals still present. Excellent stuff boys, non the less! Certainly will be interesting as to how the MetO view this winter!

[Roger J Smith]

I just wanted to mention, this forecast (including the one for North America posted on this thread) isn't doing too badly so far, if anything, almost all regions have trended a bit colder than modelled, for example, very mild conditions expected early in December were better described as milder than average, east coast of North America roughly the same (record highs did occur on Dec 3-4), and now with this cold set-up, the cold is probably even deeper and coming on a few days ahead of the predicted mid-point of this cold snap, although that could still verify if the models are breaking down the cold spell too quickly.

What, if anything, does this imply about events further along this winter? We were both saying look out for a possible windstorm around New Years Eve and a very cold, snowy interval in mid-January. I don't think the results so far take either of these down in probability, the interesting thing will be to see if the warming index combining with lifting (northwest directed) retrogression as discussed will totally flip-flop the pattern around Boxing Day or a day or two later, or whether this high energy peak (31 Dec) will have to push the arctic air as with the 1978-79 blizzards at same time of year. At the moment I would lay the odds on the milder, windstorm solution to this.

Then the second interesting point will be, does this storm just disrupt the 62-63 like block we're starting to see, for a few days, or will it blow it away for weeks as per the same event (Jan 10-11) last winter? There again, my money's on a temporary breakdown (if any) with a good chance that this month's cold and snow will either be matched or bettered in Jan 2010. If so, our conservative estimate of 3.0 for CET may bust on the high side, because anything much stronger than this outbreak would be 1987-like for sure (and kudos to Fred if that were to happen, I think I tend to be the more conservative one in our operation).

Comments about later in the winter are probably not affected by anything seen so far or projected into January. I have reasons to think that any strong blocking would take a more southerly turn than it did in 1963 by about February first.

Meanwhile in North America, the east coast cities have not seen much snow yet (just a minor event on the 5th in western suburbs of DC and PHL into interior New England, otherwise it's been all rain and either mild or cold/dry so far, a big lake effect storm a week ago hit various parts of the Great Lakes basin). However, there's a snowstorm on the horizon now with strong low pressure moving out of the Gulf and moving up the east coast. That could eventually morph into a central Atlantic low that tries to break down the block around Christmas.

Anyway, we'll see by about the 26th how big a cold event this really becomes, there's a lot of rather marginal looking thicknesses on some of the models leading me to suspect the usual witches' brew of precip types in the weekend and first days of next week outbreak, probably this would tend to keep CET values not far from zero for those days (I've learned the hard way that the 516 dm thickness needs to make aggressive contact with the BI to enforce mP type snowfalls), but wow ain't life grand now that "even larger teapot" has turned to "more modern still winter."

[Cookie]

very interesting read. RJS, isn't their always a tradition of new years eve storms?

[Roger J Smith]

Maybe, I've always thought of the period Dec 16-29 as being less stormy than either side of that time period, and I've associated it with a sort of stability pulse in the atmosphere from the Sun crossing the galactic equator (around Dec 22). It's certainly noticeable in the climate of eastern North America, not so sure about western Europe.

I mean, how often is Christmas travel disrupted by weather? Not that often in my recollection, the weather is often a lot worse just into the new year.

BTW Cookie, you must be getting excited sitting in the firing line for Saturday's front.

[Cookie]

Maybe, I've always thought of the period Dec 16-29 as being less stormy than either side of that time period, and I've associated it with a sort of stability pulse in the atmosphere from the Sun crossing the galactic equator (around Dec 22). It's certainly noticeable in the climate of eastern North America, not so sure about western Europe.

I mean, how often is Christmas travel disrupted by weather? Not that often in my recollection, the weather is often a lot worse just into the new year.

BTW Cookie, you must be getting excited sitting in the firing line for Saturday's front.

yes, Just wish I had some kind of idea how much snow is coming, I keep getting asked at work.

Back to the new years thing, always seems to be a running joke around new year in the 5 years been in scotland that the new year fire works displays in the capital get disrupted by bad weather.

[BLAST FROM THE PAST]

yes, Just wish I had some kind of idea how much snow is coming, I keep getting asked at work.

Back to the new years thing, always seems to be a running joke around new year in the 5 years been in scotland that the new year fire works displays in the capital get disrupted by bad weather.

Hi Cookie

I've been away for a few days and nice update there by Roger. It would seem that the New Year storm may get felt more someway south of you [for a change]. The signal is strong for a powerful event with stacks of precip and strong winds...so maybe just drinking then NYE?

BFTP

[Cookie]

Hi Cookie

I've been away for a few days and nice update there by Roger. It would seem that the New Year storm may get felt more someway south of you [for a change]. The signal is strong for a powerful event with stacks of precip and strong winds...so maybe just drinking then NYE?

BFTP

Hi, BFTP

Typical, I could do with a decent winter storm, thier has only been a few so far this year and we haven't hit 80 mph. thanks for the update though, I suppose a lot can change between now and then.

trying to be more postive we are rapidly approching the month where we get the most powerfull atlantic storms battering on our doors.

keep up the good work

[Roger J Smith]

Christmas greetings to all.

The trend on the most reliable models is now definitely pointing at a winter storm situation at the energy peak of the northern max (Dec 30) full moon (Dec 31) and it now appears to me that a blizzard may develop in parts of southern and central England.

For our model research and validation, this will go down as a suppressed storm track error, in other words, the consensus index values would have indicated this event moving across the British Isles on a track 3-5 deg north of where it is setting up. This is certainly consistent with the general run of events since the 15th with the strong block and very cold conditions.

Of course, there is still the slight chance of model reversal between now and then with a milder solution at the last moment. I would not be predicting that from the guidance available now. Instead, I would be concerned that a blizzard-like snowstorm will develop especially in areas open to the North Sea, but details will probably continue to evolve. There could be rain and strong winds in a few south coastal locations with this, but for almost all other districts it seems likely to be mostly snow. The situation is likely to evolve from a rain-sleet-snow banding set-up on the 28th towards the snowstorm as the gradient tightens and cold air pushes back from the north.

[Mark Bayley]

How far North would expect the precipitation to reach? The ECM and GFS have it reaching Yorkshire. Would you expect them to trend this further south, like they tend to do in this situation?

[Roger J Smith]

Mark, I am personally leaning towards any model error at this range being "too far south" types of error because if there is one minor factor (at this time range) not being diagnosed or input by the models, it could be the northward pull on the developing frontal band -- even if this amounts to only one degree of latitude (undiagnosed, that is, the actual pull is probably stronger but most of it is diagnosed already), that could tighten up this thermal gradient and push the over-running precip band as far north as southern Scotland. The general run of models today suggests a rather disorganized event that gradually evolves into sea-effect snow without large amounts of frontal precip, but there again, there may be undiagnosed deepening by 3-5 mbs. It's very much of a toss-up at this point whether we see a major winter storm, a series of minor ripples followed by some sea-effect, or some totally different solution like a strong low cutting a bit further north.

The same uncertainty is being widely discussed for what we call "timing line one" (yours is timing line three) in the northeast U.S. for the same energy peak, which the models continue to hint may explode into a strong coastal storm around the 31st, although solutions keep coming out for it that vary from the blizzard of the age to a six-hour sleet and drizzle damp squib. It all depends on phasing of the slightly separated subtropical and subarctic jet streams that are coming into close proximity near the New York-PA-NJ region.

From a research point of view, there is no doubt that there is more development in these critical timing line zones at high-energy-peak events, on a statistical basis, but how each one actually develops depends on the upper atmospheric set-up that greets the energy peak. We have an even stronger peak to look for on 30 January.

[Mark Bayley]

Thanks for the reply Will be interesting to see how far north it gets. Models seem to playing around with it at the moment shoving it a little north or a little south! The further south does seem to be better at moment in helping with long term cold.

Hope you had a good Christmas!

Edited December 26, 2009 by mark bayley

[BLAST FROM THE PAST]

RRR

You had my severe weather warning in your sig and you scoffed at it...here we are. :lol:

Hi Johnny, would love to but can't afford it this year... :lol:

Now why do I call for another two major snow events. Dates 7-10 Jan particularly for the SE with bitterly cold ENE'lies and troughs bringing very organised bands of heavy snow showers.

14-20 Breakdown zone, LPs coming from SW so SW and South UK in for battleground scenario [these dates been there since LRF was produced]. Solar driven pattern and disturbances afoot. Looking possible for further SW event and Feb looks very very on the edge.

Enjoy

BFTP

[johnny1972]

RRR

You had my severe weather warning in your sig and you scoffed at it...here we are.

Hi Johnny, would love to but can't afford it this year... :lol:

Now why do I call for another two major snow events. Dates 7-10 Jan particularly for the SE with bitterly cold ENE'lies and troughs bringing very organised bands of heavy snow showers.

14-20 Breakdown zone, LPs coming from SW so SW and South UK in for battleground scenario [these dates been there since LRF was produced]. Solar driven pattern and disturbances afoot. Looking possible for further SW event and Feb looks very very on the edge.

Enjoy

BFTP

Cheers for that Blast ! Your forecast has been extremely accurate so far, nice one !! Hope the breakdown doesnt arrive and some snow transfers west to us lot to top the coldest Dec here in 30yrs !! We'll See !!

Heading off on 23rd Jan to same place so should be good crack and a drink or 3 !!

Europe still to freeze you think or breakdown not long after us if at all??

[Roger J Smith]

Yes, blocking seems fairly robust especially on the ECM, the GFS is trying to get back to default within 10-15 days in recent runs, but that may be spurious. We're at the theoretical peak of retrogression now and in past winters I've noticed that one cycle fades then another starts up before the whole business of retrogression fades out (because the signals move equatorward and get lost in the chaos of subtropical highs). The strong high in west Siberia may represent phase II of retrogression, in which case, there is bound to be another episode of cold to follow any brief breakdowns this month, but even those may amount to very weak signals like the one before New Years did. The higher energy potential by month's end should be very interesting, I am expecting something like an inversion high followed by a return of the Atlantic as the solution there, but we'll see how nature decides to use that energy in this highly blocked pattern.

Anyway, it's not quite 1987 style yet, but there are some pretty impressive snow streamers around Newcastle today.

I'm wondering if we will see a substantial Baltic freeze in the next week or two, as patches of ice are showing up in the Bothnia region and temps both sides of the Baltic have been frigid for days now, below -20 in parts of Poland as well as in Sweden.

[BLAST FROM THE PAST]

Hi Rog, that answers my PM. For me the signal for cold return has increased and now stands at 50-50 for Feb. I'm waiting for mid month outcome to make final assessment.

BFTP

[Cookie]

Thanks for the updates guys. as always great an interesting read.

just slightly disappointing thought as this is one my favorite time of the year for big deep Atlantic storms to push in and seem like a long time off before we get them again.

[BLAST FROM THE PAST]

This LP for Tues Wed will introduce less cold air as it tries to move in. I think a degree of trust has to be given to the models particularly upto T96. It seems that generally upto Thurs we are seeing the general plan BUT it is from the weekend where we may well see changes...and I agree with TEITS here, a SW/NE split will develop. Renewed colder attack [relevant to next few days but not as deep as previous by some margin] from the east as the block re-asserts itself. LPs attacking 16-20 from SW on southerly track. The period I mentioned 14-20 has to be re-defined to 16-21, but that is small adjustment as grand scheme remains. The block all but shunted out of the way come last 5-7 days of the month ie no influence over UK as LP barrels across the centre of the UK and then the more pronounced LP coming in for the end of the month. Feb looking very, very interesting, J Bs update is interesting yet he remains with the 02/03 composite...I disagree inasmuch the deepest cold was somewhat further west than he anticipated [although still a very good call] and so there could be a renewed attack of deep cold as we enter Feb. I am reconsidering the last month of my LRF with RJS as indeed everything looks like being further west hence warm sector west of UK and cold sector more towards NW Europe. Next weekend likely for Feb outlook.

BFTP

Just re-posting post I made yesterday following on from others and seeing that its in keeping. Now the less cold we have had/having is a blip inasmuch that the calls for the cold spell to be over by the weekend and all gone by likes of Francis Wilson are incorrect. The jet is on a southerly tracking longterm holiday [seriously long] and as the sun is awakening it will send out disturbances that will buckle the pattern temporarily. Cold will renew as LPs will start cutting off and sliding SE as the southerly track re-asserts. We are not talking bitter cold but cold from this weekend starting the set up for the renewed pulse from the east. Now taking into account the great in depth posts you have seen and timings on the model thread, big buckle coming and proper end of cold from 25-31 with deep LP barreling over the UK. This will end the current/renewed eastern influence..Kaput. Now a tad earlier to post than expected but this is where I start looking for renewed cold shot. I don't know about the teles GP superbly reads and projects BUT I think they will develop into a very favourable pattern. We must as we enter Feb look to our northern quadrant, Northely and NE'ly winds will set in again with strong HP devloping over the arctic [exactly where I don't know but I suspect a similar development to what brought our last deep cold spell. I think Feb may well now develop off the back of the peak energy period end of Jan into a prolonged and very cold pattern.

The crux of all this IMO is the solar /lunar driven pattern to readily send the jetstream south. The 'sudden' model switching showing renewed cold shot next week [and will continue IMO to develop it quickly] will be GOOD example.

I'm pulling/pulled away from the mild Feb outlook at this satge. At this stage, as I have had consultations with Roger, he remains with initial thoughts and of course may still [likely] be right. BUT I have a nagging and so I'm posting my nagging.

By the way, the GFS 18Z looks a good call to me.

BFTP

Edited January 13, 2010 by BLAST FROM THE PAST