Model Output Discussion

[SMU]

T 138 on Meteociel ( I know im using the french site- but the image is good)

http://91.121.94.83/modeles/gfs/run/gfsnh-0-138.png?12

Look at the Svalbard region- pressure beginning to fill & a hefty shortwave diving South-

this *SHOULD* start to filter the cold air westwards- lets see where it all goes-

Steve

[caz100]

T 138 on Meteociel ( I know im using the french site- but the image is good)

http://91.121.94.83/...nh-0-138.png?12

Look at the Svalbard region- pressure beginning to fill & a hefty shortwave diving South-

this *SHOULD* start to filter the cold air westwards- lets see where it all goes-

Steve

hello just looked on the map....what does the purple colour mean ?? thanks new beebie here.lol

[nick sussex]

T 138 on Meteociel ( I know im using the french site- but the image is good)

http://91.121.94.83/modeles/gfs/run/gfsnh-0-138.png?12

Look at the Svalbard region- pressure beginning to fill & a hefty shortwave diving South-

this *SHOULD* start to filter the cold air westwards- lets see where it all goes-

Steve

I know this is one of our cannon fodder models but the gme increases pressure up there earlier.Lets hope this is a better sign for the euros.

http://www.meteociel.fr/modeles/gmee_cartes.php?&ech=132&mode=0

A good sign perhaps that the deep trough is filling within a decent timeframe.

[Thundery wintry showers]

Ian, I think the graphical representation of the operational output should be removed perhaps although I do realise that it can be 'fun' to look at but shockingly I think it's taken way too seriously (in terms of a few people expecting something to happen baed on it). I agree though that T192+ should remain in the emsemble outputs as the collective nature of these is far more valuable than one single run of course.

But then wouldn't the masses just check out the "control" run on the ensemble outputs as a substitute for continually using GFS's operational runs? I can see how it might reduce the extent of the problem but I doubt it would help all that much.

What about ECMWF? That one goes out to T+240 and, to my mind, seems to tend towards two extremes (usually either way too progressive, or featuring cold NE'lys sourced somewhere near Murmansk).

[markg]

first post of the 2009/10 winter ,been away down south (well midlands) but its south for me since monday and it was good to get back and see the 0600 HRS run giving a gem of and easterly from 240hrs , FI i know but there has been nothing in charts since to get excited about since last winter!

[Thundery wintry showers]

I think there will be no easterly on the GFS 12Z because the dreaded Shortwave has set up to the NE of Scandinavia which should keep that cold air bottled up to the NE. It will probably advance closer to Britain past T+264 but never make it across.

[Iceberg]

Yep Agree TWS, the 12Z will be no where near as good out in FI, for a vareity of reasons tbh.

[nick sussex]

I think there will be no easterly on the GFS 12Z because the dreaded Shortwave has set up to the NE of Scandinavia which should keep that cold air bottled up to the NE. It will probably advance closer to Britain past T+264 but never make it across.

Yes won't happen on this run but its unlikely every run would show it at this timeframe anyway, i'm still sitting on the fence here, i think the first stage is to see the trough fill, that at least happens, as for the rest well who knows!

[Stu_London]

Less cold air about generally.

Atlantic programming looks quite similar to the 06z, but to the north and NE things are as good.

[cyclonic happiness]

Right at the end of the run, there is still a good cold pool growing over Scandi, so at least there is a chink of light.

Bet this is gonna be a big warm outlier in FI?

Runs seem to be flipping from big warm outlier to big cold outlier and nothing inbetween.

Edited December 2, 2009 by cyclonic happiness

[Iceberg]

yep a cold pool over scandy and a blow torch attack for the UK, sounds familiar.....

I would still confine this to the bin though after 168Z, just like the last few runs.

[Frosty.]

GFS 12z has gone pear shaped sadly, no e'ly, no n'ly either

[Backtrack]

Lol,

Latest GFS has completley taken the Beasterly off and replaced it with rain.

[kold weather]

Very poor 12z GFS overall, we briefly get a colder few days thanks to inversions but thats blasted away into almost a proto Bartlett by 300hrs...however evolution is very close to the 06z bar one factor, the LP this time continues further east rather then retrogressing back westwards, sadly a far more likely solution...

If that comes off, then a very mild December would be a real threat IMO (7C+)...of course thats probably something of a extreme variation but in an El nino December thats not what we want to see...of course I'm suggesting this will be the pattern that does emerge but one to watch for, its like the total opposite to the 06z in terms of whats possible.

We are still early days though and the models will swing, but this run does look a heck of a lot more realisitic, and has sadly what typically does feature heavily in El Nino December's for its projected pattern, though inversion days could keep us from being very mild perhaps if it came off...

[Thundery wintry showers]

I had a sneaking suspicion that there would be an "easterly near-miss" at the end of this run...

I've seen enough to make me near-convinced that this cold continental air will spread towards Britain as we head towards the middle of December. I've seen these trends before in GFS FI and once we repeatedly see a high slipping out of the Arctic and towards N Scandinavia/Svalbard sending the cold air westwards, it's rare that it doesn't come off.

But all this counts for nothing for cold/snow lovers if the cold air doesn't get as far west as Britain and the high eventually retreats south and/or east allowing the Atlantic to push it away. At the moment I would rate the UK's chances of getting a cold easterly spell around mid-December at 10%. That of course doesn't cut out the possibility of the setup recurring later in the season but I have serious doubts about the first two-thirds of December being anything other than increasingly mild.

[NorthantsSnow]

Not as good as the last run, but I wasn't expecting an improvement when the 06z was pretty much perfect. (except it wasn't in the RT of course)

Still, not a disastrous 12z with the chance still there of something colder developing down the line. Synoptically it's still interesting.

[Radiating Dendrite]

The 12z is more progressive, the trough moves further east towards us and a shortwave stops heights building in the Svalbard region, keeping the cold bottled up further north. We end up with a blowtorch and Greece ends up cold.....usual story lol

[SP1986]

I have no idea whether the GFS is to be trusted by the 'reliable' timeframe seems to be showing some consistency, whether it pulls off is a different story though because it's been seemingly consistent and dropped the pattern just like that.

I think up to T120 is probably a good bet though!

[kold weather]

The 12z is very bad IMO, its not a total disaster but its probably the worst run for a week overall on the models I'd have to say, December would nearly be a total rightoff because the 384hrs pattern would take a good 5-10 days to evolve into something colder, not impossible but the 12z run really is not great, the only saving grace is as I said before the possible inversions that could occur, its very much like some of the mild winters of the 90s and 00s, you can get colder inversions but the milder part of the synoptic set-up that 12z shows will always be too much and skew it.

The jet pattern is really bad as well throughout this run, all it'd do is promote one Azores high up after another, possibly even giving a bartlett...lets hope this run is somewhat extreme, otherwise we look towards Jan as that pattern is monsterously stubborn once in it...

Of course, the 12z could be rubbish, we shall have to see from the others, but the 12z GFs does look somewhat similar to the 0z ECM...

[Bristawl Si]

yep a cold pool over scandy and a blow torch attack for the UK, sounds familiar.....

I would still confine this to the bin though after 168Z, just like the last few runs.

I think we need to remind ourselves that this is the 'default' position for Europe and Scandinavia thru' winter. It's normal weather for Scandinavia and the mild stuff is not untypical for the UK and N.W. europe. Some years the cold progresses west to the UK, some years it doesn't. But almost every winter it is in Scandinavia.

Sorry for the 'simple' post, but that's my limit.

[nick sussex]

Oh dear the inevitable fall out from one bad gfs run, even if an easterly does happen theres no way it would show up on every single run and expecting the exact synoptics at T-280+ is just not going to happen.

It's probably a good thing otherwise the expectations in here would have snowballed to epic proportions. The best way here is to focus on the higher reolution part of the output and look for improvements within this, the first stage to any possible easterly is for the deep trough near the uk to fill, and this at the moment looks like happening, thats it, everything else is open to changes.

People have to realize that easterlies are often the hardest things for models to forecast, many times its down to one pesky shortwave here or there that means the difference between success and failure. You can't really be sure of an easterly often till within 96hrs, even less sometimes so its going to be very traumatic if people take each FI output as gospel, moan over!

Edited December 2, 2009 by nick sussex

[Stu_London]

Lets see how many ensembles go cold before we slash our wrists.

4 cold operations in a row would have been something and the evolution to +216 was very similar to the 06z. ECM at 216 and 240 will also be a good comparison.

I do suspect however that this is closer to what will end up being reality purely because this is the sort of run we always end up with these days.

[kold weather]

Nick, the problem is we could very easily fall into a very mild and horrid pattern much akin to something like Feb 98 if we are unlucky. I grant you that probably is an extreme and to be honest I think firstly the jet is too active for that and also we are still getting enough cut-off lows to stop that.

Still I think odds are swinging in favour of mild again in a big way, and if we do go mild, odds are it'll be the whole hog blowtorch type set-up...

However as I said before I think we will see both the 12z set-up and also the Scandi high at some point, in fact wouldn't be all that surprising to see something for xmas.

[karyo]

UKMO at 144 hours: http://www.meteociel.fr/modeles/ukmo2.php?nh=&ech=144&carte=1021

No need for words!

Karyo

[nick sussex]

Nick, the problem is we could very easily fall into a very mild and horrid pattern much akin to something like Feb 98 if we are unlucky. I grant you that probably is an extreme and to be honest I think firstly the jet is too active for that and also we are still getting enough cut-off lows to stop that.

Still I think odds are swinging in favour of mild again in a big way, and if we do go mild, odds are it'll be the whole hog blowtorch type set-up...

However as I said before I think we will see both the 12z set-up and also the Scandi high at some point, in fact wouldn't be all that surprising to see something for xmas.

Everyone knows my thoughts on FI, so for me i'm not bothered at all by the gfs output, for the moment the main thing is to see the deep trough fill so thats what i'm most interested in.