Model Output Discussion - 18z - 25th Nov onward

[Continental Climate]

If GFS gets to 120 and follows UKMO i will call this as a major wobble by ECM dosent happen frequently but this could be one of those times

[dragan]

More drama than Homeland. 18z jet looks different

[Jonan92]

It does

[Continental Climate]

This is a damn good chart http://www.wetterzentrale.de/pics/Rtavn1141.png!! There is fight in this cold spell yet!! UKMO leading the charge

[nick sussex]

Phew!

OMG that was painful!

With an extra 6 hours of new data can we believe the GFS 18hrs is right here? I think we'll have to wait till tomorrow to see whether the SS Snow Cruiser sinks or heads on its way!

[Severe Siberian icy blast]

I can't believe I'm askin this but I thought if the low was stronger then it would put more pressure on the high therefore more likely to crash through it? Or is it the fact that as its stronger and sends more warm air north it strengthens the block?

[Mark Neal.]

Is it safe to come out from behind the sofa yet?

Looks better than ECM again

[Downburst]

The Irish Met use ECM as their forecasting tool - ..... I therefore always look on sites such as Net Weather for a more balanced view on things as I feel Met Eireann have all their eggs in one basket so to speak.

EWS

In the interest of fact the Irish Met use a couple of modesl. ""... Output from a number of computer models of the atmosphere is also analysed by the forecasters. For forecasts out to 48 hours ahead, our own HIRLAM is the primary guidance model. Beyond 2 days the ECMWF is the normally preferred model. To help in the very short range and nowcast range, displays of a number of modern weather radars and of METEOSAT and NOAA satellites are important tools for the forecaster.""

[Duane S.]

At least some will get a good night's sleep at least. GFS doesn't follow ECM upstream, forget the rest.

ECM

GFS

[cold snap]

Phew!

OMG that was painful!

With an extra 6 hours of new data can we believe the GFS 18hrs is right here? I think we'll have to wait till tomorrow to see whether the SS Snow Cruiser sinks or heads on its way!

Looked from pretty early on that we were okay ?

Canadian low no problem

[OldMetMan]

Will it become cold or not? The GFS seems to be pretty much out on its own today, although the GEM has some similarities. In fact, the GFS is setting up a real cold block in the longer term.

For me, the jet configuration has some interesting features that support the GFS:

In particular, note the very strong jet out of Mexico at a low latitude, merging with its northerly stream which suggests an increasing amplification of a upper trough off the US easy coast, with subsequent short-waves running E, again well S across the Atlantic.This I think would amplify the mid- Atlantic ridge and downstream trough across the UK and W Europe. This pattern is present already to a degree:

I think the other models, including the ECM seem to be favouring the US jet blasting its way NE, destroying any blocking, which doesn't seem logical given the current 500mb configuration.

It will be interesting to see if the GFS sticks to the same story in subsequent runs.

.

[Geordiesnow]

GFS also has the troughing over europe slightly further south aswell which trends a little bit more to the UKMO, this run is not as good as the UKMO but its not too shabby either.

Tomorrow morning runs will probably tell us alot more hopefully, fingers cross the UKMO will stick to it guns!

[Ian Brown]

Well T126 and the pub run has thrown the ECM and it's pals out of the bar.

Fascinating times look forward to the 0zs.

[Chris D]

Yep, the UKMO-GFS team remains! For how long though? That is the question. If UKMO verifies all credit will go to it because it by far has been most consistent so far.

[AWD]

Is it safe to come out from behind the sofa yet?

Looks better than ECM again

It's definetly better than the ECM, no question about that. All depends on how it builds the block now to see what level of cold it models for us.

[LomondSnowstorm]

I can't believe I'm askin this but I thought if the low was stronger then it would put more pressure on the high therefore more likely to crash through it? Or is it the fact that as its stronger and sends more warm air north it strengthens the block?

Stronger low =>more amplification=>neutral or negatively tilted=> more WAA reinforcing the block and more likely to obediently saunter up to western Greenland out of harm's way.

[Continental Climate]

This is truly epic model watching better than any soap, look at this chart and only at 120 http://www.wetterzentrale.de/pics/Rtavn1201.png!! Not as good as UKMO but still good. Where now for the ECM!! Do the faxes update tonite?

[Duane S.]

Will it become cold or not? The GFS seems to be pretty much out on its own today, although the GEM has some similarities. In fact, the GFS is setting up a real cold block in the longer term.

For me, the jet configuration has some interesting features that support the GFS:

In particular, note the very strong jet out of Mexico at a low latitude, merging with its northerly stream which suggests an increasing amplification of a upper trough off the US easy coast, with subsequent short-waves running E, again well S across the Atlantic.This I think would amplify the mid- Atlantic ridge and downstream trough across the UK and W Europe. This pattern is present already to a degree:

I think the other models, including the ECM seem to be favouring the US jet blasting its way NE, destroying any blocking, which doesn't seem logical given the current 500mb configuration.

It will be interesting to see if the GFS sticks to the same story in subsequent runs.

.

Great to see your views on this OMM, keep them coming please over the coming, no doubt very fraught, days of chart viewing!

[cold snap]

http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=132&mode=0&carte=1

Wow where's steve m

This is a epic chart

[snowice]

Phew!

OMG that was painful!

With an extra 6 hours of new data can we believe the GFS 18hrs is right here? I think we'll have to wait till tomorrow to see whether the SS Snow Cruiser sinks or heads on its way!

Hi Nick if you were a betting man which way, in your honest opinion do you think the ECM will go in the Morning?

[weatherguy]

I can't believe I'm askin this but I thought if the low was stronger then it would put more pressure on the high therefore more likely to crash through it? Or is it the fact that as its stronger and sends more warm air north it strengthens the block?

It's my understanding that the stronger low would send more air northwards (of course dependant on the orientation of the low) thus strengthening the block. I may be wrong though, I've only been into this for the last 3 years and am still learning!

[SMU]

Well T126 and the pub run has thrown the ECM and it's pals out of the bar.

Fascinating times look forward to the 0zs.

Ian you have to be a bit confused as I know you use the GFS as your guide-

Its a very rare occasion to have the GFS + UKMO against the ECM-

Maybe its that rare occasion where the ECM is wrong- it has wobbled before in cold spells- especially around western greenland-

S

[LomondSnowstorm]

Fairly impressive consistency between last night and tonight's GFS 18Z, considering the wider model uncertainty:

[JP1972]

Shine a bloody light.

Until/if the METO change their extended outlook, it's clearly game on for a colder outlook.

As I said in the previous thread, 2008 and 2009 cold spells had model wobbles along the way.

It's very much game on when the models are so volatile at this stage for me.

[Zenarcher]

Some good news NOGAPS 18z run has backed away from the ECM and moved over to agree with the GFS and UKMO,