Model Output Discussion - 14th - 20th November

[No Balls Like Snow Balls]

just to put an issue to bed - by this time last year, the models were counting down to the onset of the 'freeze' like clockwork. the amazing thing was that there were very few hiccups in the fi output. in fact the modelling was often more 'armageddon like' than actually transpired the naefs picked up the greenland block at T384 and never wavered. all very different to now. i'm afraid that some of you need to find another straw !!!

I think while the models struggle with what to do with the Euro block it is quite feasible that that a North Easterly could pop up within the 7 day time frame and stick, not saying snowmaggadon will suddenly appear, but we have to remember a small shift in the euro high could bring a moderate cold spell. But just as easily the Atlantic could steam roll in, we are looking at small margins here in the grand scheme of things.

Edited November 14, 2011 by No balls like Snow Balls

[nick sussex]

Thank you for your reply

You're welcome.

I really wish I could offer some hope here that we'll be seeing a big change to much more wintry conditions but the NH pattern really precludes against this for now.

However lets see what that troughing does to the west, could we be lucky and at least see some colder se'rlies or even easterlies?

If the ECM sticks to its guns and the others follow suit this evening then things could get much more interesting, experience says we won't get the high far enough north for a proper easterly, but at least the ECM offers a chance of something colder even if its just a slack se flow.

[Radiating Dendrite]

Anyone wanting a cold fix check out Ensemble 13!

http://www.meteociel.fr/modeles/gefs_cartes.php?ech=240&code=13&mode=1&runpara=0

Back to reality, the stalemate continues for now on the GFS. I was really hoping that we would start to see something colder by now, but the Euro High looks set to keep it average at best.

The ECM is interesting, but until the GFS shows some support I am not going to trust it, it has been showing the odd colder solution now and again for the past 10 days, but nothing ever seems to get close to the reliable.

[dragan]

perhaps the ECM give you and me south east flow of cooler air, still murky murky dirty little sky, my thinking is this looking at all the outcomes.

[BLAST FROM THE PAST]

I don't seem to remember the models being rock solid from this time last year of the impending freeze? Yes NAEFFS anomaly chart suggested huge HP over Greenland but the charts were far from rock solid?

BFTP

[nick sussex]

I don't seem to remember the models being rock solid from this time last year of the impending freeze? Yes NAEFFS anomaly chart suggested huge HP over Greenland but the charts were far from rock solid?

BFTP

The teleconnections all pointed to that and so the background signals were there.However for the timebeing there is absolutely no sign of any height rises over Greenland in the teleconnections or the output.

Thats not to say that the UK has to be stuck in mild weather though, the much maligned Euro high might well ride into town and prove to be the saviour!

If at that point it can hold on and theres some more amplification upstream then things might look better, as far as I'm concerned though for now its either the Euro high or mild damp sw'erlies.

Edited November 14, 2011 by nick sussex

[phil nw.]

GFS 00z showed what can happen when the the jet amplifies allowing the Hts to build towards Greenland.

Of course 006z GFS brought us back to reality with the upstream flow looking flatter again.

ECM Op. run was very much a cold run against the mean with the placement of the Euro High further North.

http://www.weerplaza..._pluim&r=midden

At present the overall pattern of Hts to our East and the Atlantic Troughing just to our West looks like remaining.

The uncertainty starts towards the weekend as to whether the Euro High becomes more of an influence or the Atlantic makes inroads into the UK.

Of the 3 main models GFS looks the most progressive with the others favouring the High nearby for a while longer at least.

As others have said the best chance of some surface cold at least is if the Euro High maintains and allows some feed of continental air from the South East if it orientates favourably.

The other option of the Atlantic pushing right across with a stronger vortex to our north would likely result in a mild zonal pattern with the Jet riding over the top which was what the models were hinting at yesterday.

Edited November 14, 2011 by phil n.warks.

[shedhead]

I don't seem to remember the models being rock solid from this time last year of the impending freeze? Yes NAEFFS anomaly chart suggested huge HP over Greenland but the charts were far from rock solid?

BFTP

This time last year the first NE'er was on the horizon and bearing down on us. I recall most if not all signals at that time were pointing towards strong, sustained N blocking.

Are you sticking by what you posted earlier this month re the last week of November, or do you intend to update mid week when the 10 days you spoke about are up?

Posted 07 November 2011 - 21:03

chionomaniac, on 07 November 2011 - 20:52 , said:

I love your confidence, Fred, but the more I look at it the more I feel that this pattern change could fall flat very quickly. Where is the ECM to go if it has got the pattern right? Not to cold I bet. More likely to a pattern where the PFJ is north of the UK and a ridge is held over the UK to its south. That is the pattern that the GFS is already considering.

As I have said previously we will need another 'kick' to a further pattern change if cold is to follow and I can't see where that kick is going to come from. Especially when the Asian MT reduces without having a knock on effect with the stratosphere which is already far cooler than average. Patience may be needed here. I would be happily surprised to see snow before the end of November - but surprise it would be.

Hi C

Firstly, I am not talking intense cold or blizzards, but cold weather and a cold set up for last week of Nov. That's still two weeks away and beyond modelling, so any failure now is well anticipated and so for me to be revisited model wise in ten days, I hope that clarifies that I do not expect cold within next ten days.

BFTP

Edited November 14, 2011 by shedhead

[danm]

I think we were slightly spoiled last year with how early the cold weather set in. People shouldn't be expecting the same to happen again this year as it was so unusual to get that much snow and such cold weather at the end of November.

The models don't seem to be offering much at the moment, but we are only in mid-November. Last year December was freezing but Jan and Feb were average. Could well be the opposite this year.

[Cheshire Freeze]

I'm not too disheartened by the models yet today. I say 'yet' as the ECM 12z will probably come along and spoil that one! Although I must say that it is encouraging to see both the operational and control of the ECM run follow a virtually identical track on the cold side of the ensembles. This says to me that either a) the control and operational are well off the correct track or b ) that the ensembles will slowly shift towards this idea of cold being advected westwards. To be honest I wouldn't like to back either of those scenarios yet.

Also, for those poo-pooing the idea of cold based on teleconnections, you don't need a -NAO to deliver cold from the east. Infact good Scandi highs in the past have come with an intense PV over western Greenland or Canada yet bitter cold has delivered over the UK.

Edited November 14, 2011 by CreweCold

[Rocheydub]

Last year December was freezing but Jan and Feb were average. Could well be the opposite this year.

Actually, IMBY, Jan was a couple of degrees colder than average, and Feb was average.

Looking forward to the GFS output this afternoon, we'll have a better idea then if ECM or even the latter part of GFS's previous run hold any substance

[Frosty.]

The Ecm 00z is not buying into a return of atlantic domination and actually looks like a dry run for the east but with the west and northwest catching some rain as lows remain slow moving to the west with the block to the east doing it's job very well and next week shows a colder continental outflow pushing into eastern britain. The Gfs 06z still shows a general breakdown to unsettled weather but it does look a little more watered down than yesterday and high pressure to the east has more impact today, meanwhile the latest meto is going with a nw/se split to develop with unsettled and windy weather for nw britain and drier, brighter and colder towards the south & east of the uk, more in line with the ecm than the gfs 06z, still no sign of snow apart from in the extended outlook for hills in the north but for that to happen, we would need some cold zoneality and the current models don't suggest any.

[snowfall09]

Actually, IMBY, Jan was a couple of degrees colder than average, and Feb was average.

Looking forward to the GFS output this afternoon, we'll have a better idea then if ECM or even the latter part of GFS's previous run hold any substance

What time does the GFS start to roll out?

[chionomaniac]

This time last year the first NE'er was on the horizon and bearing down on us. I recall most if not all signals at that time were pointing towards strong, sustained N blocking.

Are you sticking by what you posted earlier this month re the last week of November, or do you intend to update mid week when the 10 days you spoke about are up?

Posted 07 November 2011 - 21:03

chionomaniac, on 07 November 2011 - 20:52 , said:

I love your confidence, Fred, but the more I look at it the more I feel that this pattern change could fall flat very quickly. Where is the ECM to go if it has got the pattern right? Not to cold I bet. More likely to a pattern where the PFJ is north of the UK and a ridge is held over the UK to its south. That is the pattern that the GFS is already considering.

As I have said previously we will need another 'kick' to a further pattern change if cold is to follow and I can't see where that kick is going to come from. Especially when the Asian MT reduces without having a knock on effect with the stratosphere which is already far cooler than average. Patience may be needed here. I would be happily surprised to see snow before the end of November - but surprise it would be.

Hi C

Firstly, I am not talking intense cold or blizzards, but cold weather and a cold set up for last week of Nov. That's still two weeks away and beyond modelling, so any failure now is well anticipated and so for me to be revisited model wise in ten days, I hope that clarifies that I do not expect cold within next ten days.

BFTP

I think that I could repeat the post I made then but add on another week!

[tinybill]

Anyone wanting a cold fix check out Ensemble 13!

http://www.meteociel...ode=1&runpara=0

Back to reality, the stalemate continues for now on the GFS. I was really hoping that we would start to see something colder by now, but the Euro High looks set to keep it average at best.

The ECM is interesting, but until the GFS shows some support I am not going to trust it, it has been showing the odd colder solution now and again for the past 10 days, but nothing ever seems to get close to the reliable.

well got me rock salt this morning lol im ready!!!1

[No Balls Like Snow Balls]

What time does the GFS start to roll out?

about 4pm, the is a link somewhere on NW mentioning times of each model's runs.

Edited November 14, 2011 by No balls like Snow Balls

[Frosty.]

cold zoneality is also beyond current modelling apart from the occasional gfs FI tease but I get the impression that most on here are now hoping the gfs moves more towards the ecm and that the ecm continues to build on the 00z and not flip back to a milder atlantic outlook with a sw/ne tilted jet.

[Radiating Dendrite]

well got me rock salt this morning lol im ready!!!1

Think the only thing you will be spreading that on is chips!

[shedhead]

I think that I could repeat the post I made then but add on another week!

I agreed with you then Chiono and I still agree with you now. Perhaps BFTP is again picking up something we're missing, as a cold fan I do hope so, but I must confess that I'm really struggling.

Edited November 14, 2011 by shedhead

[A Winter's Tale]

How are things looking at the moment and how would the current situation affect December?

[shedhead]

How are things looking at the moment and how would the current situation affect December?

I think given the current set up we've had the mildest of this months weather, but with the 2nd half of Nov still having a 60-70%% chance of being milder than average and it's hard to see at this stage how things are going to change hugely as we go into December. So this is a bit of guesswork, but based on current signals I'd say the 1st week has a 60% chance of seeing normal temps, a 30% chance of being milder than average and just a 10% chance of being colder than average.

Edited November 14, 2011 by shedhead

[legritter]

just had wisdom tooth out , just got back from dentist and decided to cheer myself up , had a quick look at charts 10 / 15 days out ,looking like its going too be hard to predict late november . some good cold coming for those moscovians , and also some canadian territories , lets hope some good cold gets bottled up , and we can tap into some . im currently studying some old charts from my library , looking at mild sep/ oct and nov to see what followed , not guaranteed to give us a clue but i will post if i think interesting , its going to be a painfull modell watch this winter i think, especially after last decembers dream synoptics , perhaps ecm is taking us towards something , next couple of days could tell . atleast we have 12/14 weeks to dream and hopefully get our wishes granted , cheers legritter

[Frosty.]

A quick look ahead to next month on the CFS indicates a green christmas with mild winds from a southwesterly direction and no sign of snow before christmas either but patterns can change so it's not over until the...

[Summer Sun]

What time does the GFS start to roll out?

It's on it's way out now, as of 15.55 it's at 48h

[Liam J]

A quick look ahead to next month on the CFS indicates a green christmas with mild winds from a southwesterly direction and no sign of snow before christmas either but patterns can change so it's not over until the...

The CFS is also showing a big fat bartlett high over Europe into the first week of December with southerly winds off the continent, and also periods of unsettlled and stormy weather at times. CFS does like to chop and change.