Winter Model Discussion - Cold Hunting - 20th Dec

[Summer Sun]

The weather has and always will do something unexpected and go against all the rules, a computer model will never be able to expect the un-expected, there is nothing greater than mother nature, i stand by my statement.

Yes you can have the best computers and models in the world but at the end of the day Mother Nature will decide what we get

Christmas day is looking Dry, bright and breezy for most, with some wintry showers on the Scottish mountains

Those heading to the Boxing day sales like myself could be in for some snow first thing in the north and down to parts of Wales

Edited December 21, 2012 by Gavin.

[P-M]

Blimey, that really is quite a statement

With greater understanding of the physics involved - notwithstanding the ever-increasing power of super-computing - the 5-day forecast today, is as accurate as the 1-day forecast, 20 years ago.

That's with the same 'weather' - it's not some new, easier-to-read weather.

So science has evolved; our understanding has evolved, and as has the technology at our disposal. There are some processes and phenomena which are still in the infancy of understanding, and as this improves further with more research, it's these advances which correlate through to greater accuracy.

Personally, I think some people expect too much; viewing these charts out in the 5-10 day range, wonder why they hardly ever verify, then bash the models. Laughably, some even look beyond 10 days. The verification scatter plots for all models post 5/6 days are hilarious. The goal for this decade, will be to extend that confidence out to the 7 to 10-day range - at least.

Look at the Japanese. This year they on-boarded the worlds' most powerful meteorological super-computer: 847 TFlops! That'll deliver to the JMA capability for higher-res, more layers, increased range and greater scope to calculate new variables - all resulting in more accurate, detailed forecasting. That power doesn't come cheap though: $1Bn investment by JMA, hence the respect Exeter has for them. I've actually heard that UKMO and JMA will be working together to develop a brand new experimental platform by 2014, with a view to roll-out onto the UKMO's newest super-computer in 2017. I think it's going to be something along the lines of a massively scaled-up, continental UKV, with multi-member ensemble support. That's what I've heard anyway.

The demand and importance for accurate weather and climate forecasts has never been higher; not merely to provide a good public service, but because so much of business - the success and failure - rests on solid accuracy. The Met Office make a tidy sum from licensing their UKMO base platform to meteorological agencies worldwide, and they also supply bespoke services to private companies and institutions. Beyond that though, or more - beyond borders - there's been a suggestion that worldwide meteorological super-computing could be harnessed, therefore delivering a game-changing array of forecasting suites. I very much doubt that will happen any time soon though, for a number of reasons - even though the benefits are admittedly exciting.

A lot of people knock The Met Office, but the proof is in the pudding: in this tough financial climate, 'the Brits' are the preeminent world leaders in meteorology. Other meteorological agencies procure their services, and - if you read as many papers as I do - you'll see that they're frequently referenced, when it comes to peer review and due respect. They're one government agency that the British people can be thoroughly proud of, and I can't imagine how many thousands of lives their work must've saved across the world.

Good post - however no balls previous statement is logical to me - the weather controls the models - we are not in an age yet where we can programme the weather so stands to reason -

Anyway - I can clearly forget about blizzard heaven for the next while now based on todays outlook but as always things can and do turn around....forever the wishful thinker....

[CanadaAl]

Is it me or does anyone else think that massive high can't be shifted that easily? I know i'm most likely clutching at straws but models seem to move that high effortlessly east and it's gone by monday. I'm not sure it will be that easy. I'm probably wrong though

[Frosty.]

Boxing day at least looks cold as polar air spreads southeast with some wintry showers to the north and followed by a frosty night, I notice the gfs is now showing a slower change compared to the 6z as the trough takes ages to push further east so nowhere will have a white christmas if this occurs.

Edited December 21, 2012 by Frosty039

[SnowBallz]

The weather has and always will do something unexpected and go against all the rules, a computer model will never be able to expect the un-expected, there is nothing greater than mother nature, i stand by my statement.

Well, that is your prerogative.

However, your statement was that evolutions in science wouldn't make any difference. Patently, and evidenced by the advancement in accuracy over those 20yrs, that is categorically wrong. You don't have to agree with that - it doesn't matter, as it's a fact.

As an aside, if you honestly do have such a blasé view of the models, then could I ask what exactly brings you into the Model Discussion thread? If your default position is that computer models are useless, and mother nature does as she wants regardless; are you not simply wasting your time?

[SnowBallz]

Good post - however no balls previous statement is logical to me - the weather controls the models - we are not in an age yet where we can programme the weather so stands to reason -

Anyway - I can clearly forget about blizzard heaven for the next while now based on todays outlook but as always things can and do turn around....forever the wishful thinker....

Oh absolutely.

But no one is suggesting that. NWP is a predictive science; nothing to do with trying to influence the weather - which is something completely different. Everyone knows the weather is inherently chaotic - so I find it a bit 'stating the obvious' and very self-defeating to simply resign oneself to merely repeating that mantra. Thankfully, there are many who aren't as apathetic; those are the ones who have driven this science forward in those 20yrs, and given us all the appetite to wonder into the realms of monthly, seasonal, yearly and even decadal forecasting.

[bluearmy]

Is it me or does anyone else think that massive high can't be shifted that easily? I know i'm most likely clutching at straws but models seem to move that high effortlessly east and it's gone by monday. I'm not sure it will be that easy. I'm probably wrong though

Its clear that although it fought harder than expected (as all big blocks tend to) the models (especially the ens) were right to remove it over xmas week. i presume that had it only been the atlantic attacking, it may well have survived for longer, maybe won. however, those very low heights sinking south were too much for it and it bows out gracefully

[No Balls Like Snow Balls]

Well, that is your prerogative.

However, your statement was that evolutions in science wouldn't make any difference. Patently, and evidenced by the advancement in accuracy over those 20yrs, that is categorically wrong. You don't have to agree with that - it doesn't matter, as it's a fact.

As an aside, if you honestly do have such a blasé view of the models, then could I ask what exactly brings you into the Model Discussion thread? If your default position is that computer models are useless, and mother nature does as she wants regardless; are you not simply wasting your time?

With all due respect no you can't ask

[phil nw.]

Boxing day at least looks cold as polar air spreads southeast with some wintry showers to the north and followed by a frosty night, I notice the gfs is now showing a slower change compared to the 6z as the trough takes ages to push further east so nowhere will have a white christmas if this occurs.

Often the way Frosty as the cold seeps south we get trough disruption in the flow as it meets the Atlantic mildness we can see those little lows within the Low complex to our north.

This is what Nick S was alluding to yesterday with the GFS modelling these cold uppers in such a setup.They usually modify somewhat nearer the time when more detail is picked up.

May change again but these are the sort of complications that can derail things as you have probably seen yourself in the past.

The weather and the models are completely independent. The weather isn't dependent on the models, and the models aren't dependent on the weather, rather just the mathematical data they are seeded with. However, as data mesh becomes increasingly dense, it'll become more and more difficult for Mother Nature to do something unexpected, other than in FI.

Talking of which can we all get back to whats in front of us -the 12z outputs-thanks folks.

[Southender]

Light at the end of the tunnel?

[swfc]

Phew!!!possibly the worst 12z run ive seen this imo.oh well guess wev the strat warming event to hang on to in jan?

[Grimsby Snow Lover]

Greens and yellows appearing over Greenland, I wasn't expecting that. Just a pity its shown in the far reaches of FI. Wonder if this will become the new trend as the next few days/weeks progress?

http://cdn.nwstatic....312/h500slp.png

Edited December 21, 2012 by Grimsby Snow Lover

[swfc]

Light at the end of the tunnel?maybe but at 300hrs away id say doubtfull

[Summer Sun]

Light at the end of the tunnel?

Not really no.............

[IDO]

The Boxing Day northerly/Nw'ly toppler now not extending further south than Birmingham according to the GFS 12z. Accordingly the uppers for the north are not so cold and the snow risk is reduced. Similar to the UKMO this morning and trending towards the non-event of the ECM. Still seasonally cool/cold over Christmas/Boxing Day.

This allows the Azores High to ridge NE towards the UK quicker drawing in milder air to the SW by late Thursday:

http://cdn.nwstatic....150/h500slp.png

You dont need a chart for the rest of the run, but here's one anyway:

http://cdn.nwstatic....159/h500slp.png

Not much cold likely from there: http://cdn.nwstatic..../h850t850eu.png and mainly wet and windy for all. Whilst the Azores High is the main player for the UK little chance of sustained cold with nominal chances of snow for the south but maybe some for sea-level areas up north.

New Years Eve should be mild in the south: http://cdn.nwstatic....240/h500slp.png and http://cdn.nwstatic....2/ukmaxtemp.png

A wet New Year: http://cdn.nwstatic....ctypeuktopo.png Possible a 1/2 day toppler for the north ( ...). But well into FI by then and likely to be downgraded nearer the event.

No changes then, still a zonal wet and windy mildish (IMBY) outlook.

Edited December 21, 2012 by i'm dreaming of...

[phil nw.]

It usually the case in an Atlantic pattern like this that the models seem to have better agreement for a few days out and there`s really nothing between them up to T120hrs.

From a cold point of view it`s frustrating to see those deeper blues on the 850hPa charts just lurking to the north of Scotland.

http://modeles.meteo...nh-1-120.png?12

A little upstream amplification of the jet would make all the difference as it could sharpen the Atlantic trough allowing better transport south of that polar air-at least for a short while until the next low moves in.

The pattern is so darned flat and the stream of lows just keep coming towards us and it`s difficult to see any ridging holding for more than a few hours.

[A.J]

Afternoon folks.....Just for folks who can't differentiate between FI & F1.........Interesting news from the world of Grand Prix racing.........Just had a wonderful xmas present from Bernie Ecclestone...the new CFS sponsored F1 Calendar for 2013.....

January....

February.....

March.....

bring on March!!

[BLAST FROM THE PAST]

It has been for some time now suggested that Xmas will be Green generally and active with LP in charge. So the models are suggesting...yes Green and LP in charge. Some posts of disappointment would seem that a snowy Christmas has been on the cards and taken away from us. It hasn't and there's no likelihood of a sudden change to bitterly cold snowy weather either IMO. I like very much what I'm seeing bigger picture wise though and a GHP building is an area to watch into New Year if you're hunting cold. GFS deep FI throwing this idea up now, but it will be deep FI for a while yet IMO as I think timing we are looking into 2nd week of Jan. There is massive widespread cold over nearly the whole of Russia and Scandinavia, some reports saying deepest winter for decades so that is some serios cold pool.

The here and now is the ever evident flood threat, this could be a troublesome build up to Xmas and indeed could be a mini disaster for some.

BFTP

Edited December 21, 2012 by BLAST FROM THE PAST

[J10]

Afternoon folks.....Just for folks who can't differentiate between FI & F1.........Interesting news from the world of Grand Prix racing.........Just had a wonderful xmas present from Bernie Ecclestone...the new CFS sponsored F1 Calendar for 2013.....

January....

February.....

March.....

bring on March!!

If this thread was about about F1, we would be going round in circles never getting anywhere.

Actually at times that is not far off the case.

[Duane S.]

I very much like the 12z. FI or not has the GFS picked up a new signal? It's the first time I've seen one build up fairly good heights in Greenland like that for a good few weeks now and that would be about the time that that could occur (at the earliest) IMO.

Plenty of weather to get through before that but I strongly suspect the start of the next rollercoaster episode is about to commence.

[Frosty.]

The Gfs 12z has a nice FI with cold air flooding the uk instead of torrential rain, wintry showers and frosty nights hopefully to start the new year, next week shows colder air slowly pushing southeast by boxing day but then becoming milder and more unsettled from the southwest towards the end of next week but then colder once the trough moves away to the east.

[Grimsby Snow Lover]

For what its worth tonight GFS 12z ensembles don't seem as cold as the previous set. The search for prolonged cold continues...

http://www.wetterzentrale.de/pics/MT8_Aberdeen_ens.png

http://www.wetterzentrale.de/pics/MT8_Manchester_ens.png

http://www.wetterzentrale.de/pics/MT8_London_ens.png

[Summer Sun]

For what its worth tonight GFS 12z ensembles don't seem as cold as the previous set. The search for prolonged cold continues...

http://www.wetterzen...berdeen_ens.png

http://www.wetterzen...chester_ens.png

http://www.wetterzen..._London_ens.png

Yes the Aberdeen ensembles are looking much warmer than yesterday as 2013 begins after a cool down between the 26th and 29th or 30th there than becomes a lot of scatter with the members more are trend above zero than they were yesterday

[IDO]

The Gfs 12z has a nice FI with cold air flooding the uk instead of torrential rain, wintry showers and frosty nights hopefully to start the new year, next week shows colder air slowly pushing southeast by boxing day but then becoming milder and more unsettled from the southwest towards the end of next week but then colder once the trough moves away to the east.

Looks like the op at that time is a relative cool outlier:

http://www.meteociel...1&ville=Londres

The GEFS mean at that time:

http://modeles.meteo...21-0-300.png?12

Average uppers for the south and normal for the north.

Edited December 21, 2012 by i'm dreaming of...

[cooling climate]

Browsing through the GFS ensemble members there is a majority that are picking

up higher pressure (blocking) to the north and over the Arctic in the extended

range. Hopefully this will be a continuing trend in the future.

Looks like the op at that time is a relative cool outlier:

http://www.meteociel...1&ville=Londres

The GEFS mean at that time:

http://modeles.meteo...21-0-300.png?12

Average uppers for the south and normal for the north.

So thats average for the north and south then lol.