Model Output Discussion

[weather eater]

We all need a little luck and it seems I've had a lot of luck this Nov and winter.....for folk that like strong winds and heavy cold rain[as I do] lets hope for more!! The set up and proposed set up for me screams of the jet angling southwards again and the models are certainly hinting that way. It is of course still FI BUT what we have seen this winter and how things quickly develop then T120+ has to be viewed with suspicion and one needs to add instinct, experience, differing methods, teles etc. Even next Wed is not set in stone...very interesting times. I tell you what it was pretty chily today and it is cold right now...I'm supposed to be under fog and +2c tonight...I reckon sub 0c is on.

Another angle coming from 12z ECM, looks chilly 144 to 168. Many twists and turns to come.

BFTP

Clear and dropping here as well, although today has felt very mild. I'd be happier if I could see real signs of the ECM coming on board, maybe tentatively so this evening. Still it will be a slow evolution with plenty of twists and turns.

[cooling climate]

ECM t240 is an excellent chart that would definitely lead to a potent very cold spell

of weather but again it is just about the trends for now.

As with the last two cold spells when blocking establishes over the Arctic it takes a

while to model correctly where the residue pieces of vortex move to if indeed we see

another split vortex, which I have to say is looking very likely again.

I did say yesterday to expect to see this in the next day or two but if we do in fact see

a MMW then northern blocking post t240 could develop even quicker and more intense

than is already being shown.

[Severe Siberian icy blast]

Yes some did but others like myself didn't.

ECM 12Z is a run full of potential, the kind of run in winters past we would all get excited over but due to how good this winter has been so far we are less interested.

Not much mild, wet and windy weather on that run that's for sure.

Feels chilly right now, some mild spell

Couldnt agree more , yes todays been milder , as have the lat 2 days or so , but mild, certainly not , there were comments made based on emotions rather than logic at times , although the models wanted to bring milder weather over a longish period , the cold was never far away and now looks like we are on the brink of another wintry spell . Things can change we no that , but the -ao and strong blocking hights i dont really see many other options tbh . We can fall on the wrong side of the high yes , but i feel even if that was the case then it would still advect cold westward at times followed by battle ground situations .

Back in november the there was a long range winter forecast i watched by some american chap on the news in the us , (forgot names) but he did predict above avarage snowfall for england especially , and also said of the uk been the area for the battles between cold and mild air to take place .

Got things clock on so far.

[nick sussex]

A very encouraging ECM run which keeps the block initially and then drives the trough se into Europe, the 240hrs is close to being very good but I think we need to take small steps within the more reliable timeframe. I think looking at shorter term changes works well when viewing the model output.

Also nice to see the bbc upgrading the snow potential for mid week and quite glad this might muzzle some of the critics who were berating me a few days back for calling a possible snow event! There was alot of talk regarding mild and wet in here for the last few days, as far as I can see it looks close to average with some colder interludes.

So overall some positive signs this evening but to be honest I'm more interested in the output upto 144hrs, lets try and squeeze as much fun and games out of the ridge extending from the Siberian block. A little shift west with the pattern could make the end of the week also interesting.

[Ben_Cambs]

im skeptical tomorrow is likely to be total oposite.

models are not handling things very well im not saying this for any other reason than to be carefull of the hype,

its nothing like the setup just gone so id expect anything cold to be a fleeting visit.

im still in the opion that tonights outputs are rather to much of a backtrack perhapes and i hope im wrong.

im now 70/30 mild will dissapoint us.

I disagree with you, it has come up on the past 4/5 runs on the major models in favour for a colder spell, theres plenty of factors to "aid" the spell, such as Arctic blocking, which is more prevelant in Feb. GFS suggests the spilting of the PV by T+132, which is very good. the NAO is expected to go well into negative territory by 25th. Its not a trend yet and its in FI, but it is coming more of a feature to the models. Dont forget in late November the models picked up a cold spell in Mid December, deep in FI and they were right.

The thing is now will this become a proper trend? We will see over the next few days...

Edited January 17, 2010 by Snowman0697

[January Snowstorm]

I must be reading the charts wrong, all I can see is mild for the foreseeable with a fair chance of a bartlett high in a weeks time.

Not that i'm too bothered as the severity of the recent cold spell has left a serious toll on a lot of folk either personally or professionally.

[weather eater]

im skeptical tomorrow is likely to be total oposite.

models are not handling things very well im not saying this for any other reason than to be carefull of the hype,

its nothing like the setup just gone so id expect anything cold to be a fleeting visit.

im still in the opion that tonights outputs are rather to much of a backtrack perhapes and i hope im wrong.

im now 70/30 mild will dissapoint us.

I think the models are doing OK BB, its just since the cold spell started just before Christmas we have got rather used to milder conditions being stuck in FI and thus of no real concern, now we are looking for a return of the cold in FI and its not so comfortable viewing. There's a signal there but its not within a range that the models can get to grips with yet, pretty fascinating IMO.

Edited January 17, 2010 by weather eater

[Severe Siberian icy blast]

im skeptical tomorrow is likely to be total oposite.

models are not handling things very well im not saying this for any other reason than to be carefull of the hype,

its nothing like the setup just gone so id expect anything cold to be a fleeting visit.

im still in the opion that tonights outputs are rather to much of a backtrack perhapes and i hope im wrong.

im now 70/30 mild will dissapoint us.

Fair enough , however . . . im not sure weather this means anything and it may be coincedence but believe it or not i knew who had post this before i looked at your name as i rarely read upbuilding posts from you , maybe its living on the south coast and it makes you annoyed missing out on a lot of snow , i no it would me , but you are very negative !! Im not having a dig at you , just commenting on an observation iv made .

Edited January 17, 2010 by shaun wilmer

[weather eater]

Has any High over the Iberian peninsular now become a Bartlett, how fascinating?

[chionomaniac]

ECM t240 is an excellent chart that would definitely lead to a potent very cold spell

of weather but again it is just about the trends for now.

As with the last two cold spells when blocking establishes over the Arctic it takes a

while to model correctly where the residue pieces of vortex move to if indeed we see

another split vortex, which I have to say is looking very likely again.

I did say yesterday to expect to see this in the next day or two but if we do in fact see

a MMW then northern blocking post t240 could develop even quicker and more intense

than is already being shown.

As you say the residual vortex modeling is critical. What is encouraging is that we are seeing this disruption to the PV at a time when the phasing of the MJO could be very favourable indeed. Good trend from the ECM that we will need to see continued to have a chance of renewed cold further down the line.

[ANYWEATHER]

Encouraging, signs for a cold spell down the line, but the short term looks pretty wintry!

[karyo]

A very encouraging ECM run which keeps the block initially and then drives the trough se into Europe, the 240hrs is close to being very good but I think we need to take small steps within the more reliable timeframe. I think looking at shorter term changes works well when viewing the model output.

Also nice to see the bbc upgrading the snow potential for mid week and quite glad this might muzzle some of the critics who were berating me a few days back for calling a possible snow event! There was alot of talk regarding mild and wet in here for the last few days, as far as I can see it looks close to average with some colder interludes.

So overall some positive signs this evening but to be honest I'm more interested in the output upto 144hrs, lets try and squeeze as much fun and games out of the ridge extending from the Siberian block. A little shift west with the pattern could make the end of the week also interesting.

Agreed Nick, next week is looking interesting! Chilly overall with more than one chance for snow. I am very encouraged once again!

Karyo

[lorenzo]

Anyone mention cold FI..... Siberian block collapsing after being chased down by a split polar vortex = very cold start to February..

[LomondSnowstorm]

I don't understand the pessimism on this thread at all - nothing blowtorch mild or even above average about these charts at all, in the short or long run - http://en.vedur.is/photos/atlant_evr_hitaspa/100117_1200_216.png

http://charts.netweather.tv/gfsimages/gfs.20100117/12/96/ukmaxtemp.png

http://www.wetterzentrale.de/pics/Rukm721.gif

http://charts.netweather.tv/gfsimages/gfs.20100117/06/228/h500slp.png

http://en.vedur.is/photos/atlant_evr_hitaspa/100117_1200_72.png

Most runs are fairly cold with -5 uppers never all that far away from northern and eastern Britain. If people are expecting much better than this after the cold spell we've just had then they're living in the wrong climate!

LS

[Frosty.]

A very encouraging ECM run which keeps the block initially and then drives the trough se into Europe, the 240hrs is close to being very good but I think we need to take small steps within the more reliable timeframe. I think looking at shorter term changes works well when viewing the model output.

Also nice to see the bbc upgrading the snow potential for mid week and quite glad this might muzzle some of the critics who were berating me a few days back for calling a possible snow event! There was alot of talk regarding mild and wet in here for the last few days, as far as I can see it looks close to average with some colder interludes.

So overall some positive signs this evening but to be honest I'm more interested in the output upto 144hrs, lets try and squeeze as much fun and games out of the ridge extending from the Siberian block. A little shift west with the pattern could make the end of the week also interesting.

hi nick,

I don't know who was berating you but this could still go either way, the ecm 12z is encouraging but then I thought the ecm 00z this morning was pretty good but I was in the vast minority.

[weather eater]

I don't understand the pessimism on this thread at all - nothing blowtorch mild or even above average about these charts at all, in the short or long run - http://en.vedur.is/photos/atlant_evr_hitaspa/100117_1200_216.png

http://charts.netweather.tv/gfsimages/gfs.20100117/12/96/ukmaxtemp.png

http://www.wetterzentrale.de/pics/Rukm721.gif

http://charts.netweather.tv/gfsimages/gfs.20100117/06/228/h500slp.png

http://en.vedur.is/photos/atlant_evr_hitaspa/100117_1200_72.png

Most runs are fairly cold with -5 uppers never all that far away from northern and eastern Britain. If people are expecting much better than this after the cold spell we've just had then they're living in the wrong climate!

LS

Who's being pessimistic, I rather think the opposite is happening, most regular model watchers can see the potential, I think.

[J10]

It seems to me, the mild weather is being put back into FI, the output from tonight shows why the Met Office has put their warnings out for midweek. The ECM seems to be a very good run, and the PV seems to be wanting not to stay that long over Greenland.

Certainty it seems to me plenty of potential for some cold weather in the medium term, and given the trend of this winter, this has to be taken seriously.

[shotski]

A question for the Dons if I may, Deep in Fi on the latest GFS run it appears to show high pressure to our west and low

pressure to our east. this looks very strange to me, or am I reading the charts wrong. Help

[LomondSnowstorm]

Who's being pessimistic, I rather think the opposite is happening, most regular model watchers can see the potential, I think.

Sorry weather eater, only read up to page 6 of the thread, when the mood suddenly became more optimistic due to an encouraging set of 12Zs!

It does look quite promising for cold in the medium term, though of course the real cold is too far out for us to get too excited about yet!

LS

[Tim Bland]

After the latest outputs the evening country tracks forecast has further upgraded midweeks snow risk - http://www.youtube.com/user/terratec365

All this talk of FI and little discussion on this weeks baffles me! The above forecast also has snow on Thurs turning to rain but this could easily be upgraded if the block can resist a little more. I would rather we kept these battles going on for as long as possible!

Edited January 17, 2010 by Tim Bland

[damianslaw]

In the short term its trending cold again, we are hardly in a mild spell right now even with temps only just around average.

Tuesday to Thursday is looking a rather cold period for much of the country, some northern parts of Tuesday will struggle to see fog clearing which will supress the temps here.

Wednesday will see those colder uppers advect westwards and I can understand the BBC putting out an advisory for snow in northern and central parts, amounts and duration and location will depend on where the precipitation is most intense I feel, the shortwave looks like it will stall somewhat helping to engage the colder air in the east. Thursday could see a further bout of frontal snow though this looks rather brief.

Beyond thursday a very temporary mild spell looks on the cards as we see a milder atlantic flow, though only just above average mind, double figure maxes do not look like occuring.

Longer term - negative trending AO and NAO, more energy going into the southern arm of the jet and with the PV pulling out og Greenland a split jet looks likely, the colder air will be triggered by a southerly tracking low with northern blocking becoming evident in the last week of the month and with strong heights to the NE and plenty of cold to tap into, longer term prospects to me speak cold if not very cold.

[bluearmy]

reading the latest NOAA chit chat reassures me wrt to the lack of cold runs on the ecm ens

THE NAEFS BIAS CORRECTED

COMBINATION OF GFS AND CANADIAN ENSEMBLE MEMBERS SEEMS A BETTER

MATCH TO BLEND WITH THE 00 UTC ECMWF THAN FLATTER 00 UTC ECMWF

ENSEMBLES. PREFER EVEN A LARGER NAEFS ENSEMBLE DOSE INTO NEXT

WEEKEND. THIS IS ESPECIALLY AS AT LEAST A SOMEWHAT MORE AMPLIFIED

THAN 00 UTC ECMWF SRN STREAM FLOW FROM THE PACIFIC INTO THE US

SEEMS PRUDENT CONSIDERING LATEST WATER VAPOR AND BLENDED TPW

LOOPS...A TREND NOW BETTER SUPPORTED BY THE 12 UTC ECMWF.

Tim - i'm surprised at your comment re the cold and no precip after what we've just been through. get the cold in and the snow will follow.

[Ben_Cambs]

GFS 18z coming out soon, the question is, does it start a proper trend?

[Duane S.]

I think we have to take note when such projections come from the BBC/METO. They realise this is not your standard winter, a bit late but they got there, and have been giving more weight to cold winning out than mild for the past week or so (relative to what you might expect from them anyway). Personally, I still think the Atlantic will get through eventually (exactly in what guise i'm not sure though) but - when there is a block of that size sat there coupled with even more impressive NAO, AO and MJO projections from today, then the least you can do is have is an open mind.

[john mac]

I don't understand the pessimism on this thread at all - nothing blowtorch mild or even above average about these charts at all, in the short or long run - http://en.vedur.is/photos/atlant_evr_hitaspa/100117_1200_216.png

http://charts.netweather.tv/gfsimages/gfs.20100117/12/96/ukmaxtemp.png

http://www.wetterzentrale.de/pics/Rukm721.gif

http://charts.netweather.tv/gfsimages/gfs.20100117/06/228/h500slp.png

http://en.vedur.is/photos/atlant_evr_hitaspa/100117_1200_72.png

Most runs are fairly cold with -5 uppers never all that far away from northern and eastern Britain. If people are expecting much better than this after the cold spell we've just had then they're living in the wrong climate!

LS

I dont think people are being that pessimistic even Stephen Prudence said that we could be in for an even colder spell than the last one, Thats an acheivemnet in itself sorry stephen