Winter Model Discussion - The Hunt For Cold - 12th Dec

[Weathizard]

Anyone have the EC32 or a link too? Surely though, we should now, if the GFS was onto something with its runs yesterday, we'd be starting to see some very cold ensemble runs in the GFS suite? But to my eyes there is nothing really cold

[southbank]

well some tentative signs of a possible trend in NWP for colder soultions appearing around xmas times , hopefully we can build on these in the coming days , from a POV i happily sarcifice the rest of winter for one decent proper shot of a christmas card type of xmas with a few inches of powdery snow on the big day , been 40 years waiting !!!

[TEITS]

Losing the battle on this run in high res, but we are still in the war!

Excellent way of describing the current model output. Im not sure if I have the stamina to follow this though!.

Just want to add that I don't expect the Met O to change the outlook until we see the differences resolved. They might highlight some uncertainity though instead of being confident of the weather over Xmas.

[No Balls Like Snow Balls]

It really really could swing both ways, I can't remember a time where things are so finely balanced.

[nick sussex]

Don't worry about the lower resolution GFS here in terms of flattening the pattern out, if you hold on to enough amplification upstream you will get the undercut.

My Xmas Miracle has now stopped shipping water, we have repaired the hole and wait to see tonight if we get hit by a torpedo or whether we continue our journey to the promised land.

[bluearmy]

Given the delicate balance in the mid range, i would trust the ecm op more than normal in the day 5 to day 8 timescale. also, i doubt the gfs op will cope with the change in resolution post T192 very well. all very interesting. would like to know MOGREPS take on next week.

EDIT: significant NH profile at the back end of the run which looks like an immediate trop response to the probable warming. sterwart mentioned this in the strat thread last night and its sort of where i was coming from with my tumbling vortex idea.

Edited December 14, 2012 by bluearmy

[Methuselah]

To bin or not to bin the GFS low res: it doesn't produce any snow; but it does scream potential?

[Troubleatmill]

I think at the end of the run (total fiction i know) we are looking at what could happen if the block to the east does release its grip on Russia and Scandi, if it doesnt retrogress we really need to see the back of it and allow lows to get through or we could stay like this for a long long time, the Atlantic will always send lows, maybe this is the way forward?

[Ian Brown]

A frustrating but interesting 06z nonetheless, it's an old school battle between the Atlantic and the stubborn heights to the NE.

Anyone old enough to remember how the eighties will recall how often the Atlantic would end up being pushed back and there was great uncertainty then until the set-up was T72-96. Unfortunately more recent battles have ended up with the Atlantic marching into Poland, so more runs needed as they say. The 12z is often the most progressive run of the day so that might not see such a close battle.

[EML Network]

I know this is deep into FI territory, but isn't this yet another complete Split Vortex ??

With an Arctic High too boot ??

[Snowman.]

Best run yet for far FI, in terms of are easterly in time for Christmas I'm not getting my hopes up.

BUT definite trend for High pressure over the pole along with the other trend for a significant warming at 10hpa.

If we could establish a firm ridge into Greenland then we could be looking at some cold times.

FI yes but the trend is still their.

One thing that could go wrong is a shortwave spawning from the Canadian part of vortex going straight into are block similar to what happened in November.

Edited December 14, 2012 by SN0WM4N

[Frosty.]

There is more and more likelihood of trough disruption over the uk next week which opens the door to the cold block once again, the atlantic is not exactly going to be breezing through as it would like in the days ahead, cold air looks like returning from the northeast and there is some support for that now, we are not looking at a mild outlook, positive signs from the ecm 00z and gfs 6z for cold air to strike back.

[UV-RAY]

There is more and more likelihood of trough disruption over the uk next week which opens the door to the cold block once again, the atlantic is not exactly going to be breezing through as it would like in the days ahead, cold air looks like returning from the northeast and there is some support for that now, we are not looking at a mild outlook, positive signs from the ecm 00z and gfs 6z for cold air to strike back.

I shall remain sceptical Frosty after the last two flops, there are signs of the heigh retrogressing towards Greenland way out in FI, now that is something that wets my appetite.

[Chess01]

There is more and more likelihood of trough disruption over the uk next week which opens the door to the cold block once again, the atlantic is not exactly going to be breezing through as it would like in the days ahead, cold air looks like returning from the northeast and there is some support for that now, we are not looking at a mild outlook, positive signs from the ecm 00z and gfs 6z for cold air to strike back.

a few days ago thought you was saying no chance for cold for the next two weeks

[Frosty.]

I shall remain sceptical Frosty after the last two flops, there are signs of the heigh retrogressing towards Greenland way out in FI, now that is something that wets my appetite.

I'm more optimistic than yesterday because we had an excellent ecm last night and a good ecm 00z and positive gfs 6z, I do now think there will be disruption to the troughs over the uk next week with the cold block in a position to strike back at any sign of weakness, it's game on for next week and beyond as far as i'm concerned, even the gfs 00z showed the cold block just over the north sea on 30th december.

Edited December 14, 2012 by Frosty039

[Chess01]

See i knew people would come around from this negativity . The models have flipped yet again which people a few days ago said no chance to . I know they can flip to mild again but i just cant see it playing out the way the gfs shown a few days ago . Think we should watch out for the xmas week because the longer it goes on the more chance of proper cold spell happening because the strat is warming . Good times

[MR EXTREMES]

ive just been through all the model outputs and im not convinced the zonal train is going to continue for the duration of the runs.

thats a pretty impressive block into ne europe and even shows signs of gaining strength.

the jet at the moment seems to be our friend if cold is what your looking for.

remember how quick the fi cold spell this week came into the realiable whos to say this active alantic could lose energy fast more so if the vortex gets to its rest place quicker.

im not ramping but i think a change is coming sooner than later maybe not for atleast a week but shortly after.

[nick sussex]

My updated snow potential ratings in terms of potential and factored forward, no waffle just straight to the point!

ECM Good

UKMO Fair to middlin

GFS 06hrs Good 00hrs Yuk

The lesser lights

GEM Could do better

NOGAPS 06 00hrs combo Fair bordering on underwhelming

CPTEC Brazilian Once again fails to come out properly, apparently someone spilled a Pina Colada on the hard drive!

My optimism rating 6/10 this rebounds after being close to emergency 5 rating.

The new Holland shortwave factored in rating

Uncertainties remain here between the models but this is a key factor in terms of having a good start, so a westwards correction and a clean shortwave ejection with some ridging backing west my optimism rating hits 6.5/10!

A bit of waffle now!

There are uncertainties upstream with how amplified the pattern might become, this is crucial later as we would need to see some sharpening of troughing to the west to aid energy heading se'wards, however its also to do with timing.

If we get a good start with a negative tilt to the trough and this held to the west of the UK digging south then east USA coast amplification will probably lead to an undercut with easterly/ne flow.

So there is a decent trend across some outputs but others look less interesting, the ensembles so far are reluctant but generally in these situations they follow the operational output not the other way round.

We hope for the best this evening.

Edited December 14, 2012 by nick sussex

[pureasthedriven]

a few days ago thought you was saying no chance for cold for the next two weeks

As Churchill once said, 'When the facts change, I change my mind.'

It's allowed!

[Frosty.]

a few days ago thought you was saying no chance for cold for the next two weeks

the models have improved since then, simple as that really.

[Mark Parsons]

a few days ago thought you was saying no chance for cold for the next two weeks

As it stood a few days ago the charts where throwing up senarios that were anything but cold! Now the charts are churning out possibilities of some colder air moving back West in FI. I wish that some of you would read and understand what is being said at the time by the likes of frosty039, after all he is not god!!!! For these reasons I only post when necessary, I don't want to be deemed a god by those who can't digest what they read!!! Sorry rant over!

[Chess01]

As Churchill once said, 'When the facts change, I change my mind.'

It's allowed!

its allowed but im just stating that people should not write off the next month based on a few model runs. They will change let this be a lesson to be learned

the models have improved since then, simple as that really.

exacly thats why people shouldnt come out with comments like " no sight of cold for the next month"

[Frosty.]

its allowed but im just stating that people should not write off the next month based on a few model runs. They will change let this be a lesson to be learned

exacly thats why people shouldnt come out with comments like " no sight of cold for the next month"

there is something called reacting to what the models show at thattime, it happens during the course of every model run on here. I have more hope now because the models are indicating more of a battle ahead. Edited December 14, 2012 by Frosty039

[Mark Parsons]

there is something called reacting to what the models show at any given time, it happens during the course of every model run on here. I have more hope now because the models are indicating more of a battle ahead.

Mate, are you near a brickwall, i'd use it, you will get more sense!!!!!!!! Edited December 14, 2012 by Bridport snow

[pureasthedriven]

there is something called reacting to what the models show at thattime, it happens during the course of every model run on here. I have more hope now because the models are indicating more of a battle ahead.

Which is all the MetO do really, in their extended forecasts. They called a cold and snowy festive period a while back - because that was what was being modelled - and now they're not, because it isn't being modelled.

We're such a slave to the jet in this country, it's rarely going to be straightforward - at the moment, the jet profile at worst shows potential and at best, can help advect cold westwards via taking LP into Europe. That's all I look out for really at times like this, as if the jet can't weaken, split or dive south of the UK, it ain't going to happen.