Model Output Discussion 1st January 2014-06z onwards.

[Hotspur62]

12z GFS ensembles are actually better than yesterday's . 14 out of 23 GEFS members have snow conducive upper air over se eng 17th Jan. (yesterday it was 12). hope remains

Exactly why Coldies should stay positive(That is 61% of members).All Models having great difficulty with future set up as they always seem to when a potential Easterly is in the fold.Where is SM when you need him as would be interested to hear his take on next weeks set up. 

[Downpour]

Your spot on

Thought so. I think scatter is the big message here – looks like a right dog's breakfast albeit with the Op and the Control towards the mild end if not without some support. 

[bradymk]

Disappointing afternoon for cold weather in relative terms to yesterdays 12z runs but GFS ENS prove this is not a done deal by any means yet and GEM still colder than the rest. Over to you ECM...

[Mucka]

I may be reading those wrong, but looks as if the Op was on the mild side of the suite. 

 

It was but if it was on the mean would it be good? Even if it were among the cooler members it wouldn't be good IMO, hence not a pretty sight.

I won't even compare them to yesterdays 12z to qualify things further.

They are a poor set of ensembles if you are looking for a cold spell (doesn't mean they are right though and I'm not saying they are)

Don't shoot the messenger guys.

Edited January 9, 2014 by Mucka

[bradymk]

ECM at 72, low pressure not as negatively tilted as yesterday however better than UKMO and GFS

[LomondSnowstorm]

A few degrees more negatively tilted troughing on the ECM compared to both the UKMO and the GFS, slightly better WAA as well (although not as good as yesterday's to this point). Should have more of a chance at the undercut although it depends on how rounded or otherwise the low is modelled:

(not jumping to early conclusions, just pointing out slight but potentially significant differences early on).

[Gaz1985]

Anyway Manchester 12z ens look milder than the 6z

 

[That ECM]

http://images.meteociel.fr/im/8515/ECH1-72_hqz8.GIFDoes it stay intact or not? T96 might produce smouldering pants!

Of course we can, it is part of the fascination!

Edited January 9, 2014 by Paul

[SMU]

Well the ECM at 96 is not quite as bad as the UKMO- not as deep on all the lows.

 

 

http://www.meteociel.fr/modeles/ecmwf/runs/2014010912/ECH1-96.GIF?09-0

 

Will it be enough to create some bend to the EAST in the isobars at 144-

 

S

[Tim Bland]

Good news about the GFS ensembles is that there are plenty of cold members, bad news is that the control run follows the op, in fact it is milder

[Mucka]

Best of the main three out to 96h with a bit more energy undercutting.

 

[cooling climate]

looking at the models the ECM 0z at t168 does not look a million miles different

from the UKMO at t144 this evening.

 

[Cecil Hogmanay Melchett]

Best of the main three out to 96h with a bit more energy undercutting.

 

I just cant figure out why we are seeing virtually no undercutting at this point? Looks primed for an undercut.

[Matty M]

ECMWF not a disaster @ 96hrs. Quite similar to last night's 120hrs

 

[weather eater]

Seems to me the crucial stage is in regards the shape and track of the low pressure system at 132 hrs, now that may well resolve itself this evening but we are not going to know for sure for a couple more days.

[Mucka]

Good news about the GFS ensembles is that there are plenty of cold members, bad news is that the control run follows the op, in fact it is milder

 

Are you sure Tim? There are only 4 members that briefly get below -6 850's as far as I can see.

 

Central England.

http://www.meteociel.fr/cartes_obs/gens_display.php?ext=1&x=255&y=82

[Mucka]

I just cant figure out why we are seeing virtually no undercutting at this point? Looks primed for an undercut.

 

Well it is there, just not easy to pick out in 24h steps but the block would sink SE with energy going over the top NE if it wasn't there of course.

 

[Captain Shortwave]

this might be good enough for snow

[SMU]

120 Chart

 

http://www.meteociel.fr/modeles/ecmwf/runs/2014010912/ECH1-120.GIF?09-0

 

JUST ENOUGH UNDER NEATH

 

[Matty M]

Okay, certainly a trend to increase the intensity of that low south of Greenland near 120hrs tonight from all models.

 

However ECMWF is not quite strong with this signal. Which is good, but certainly a move away from last night's excellent output,

but the better for cold prospects than the UKM & GFS

 

[Tamara]

ECM at day 5

 

 

 

 

I think this sums up the fact that as some of us keep saying this will roll on yet before anything is decided

 

The point being it makes whatever is shown after this time open to changes - we've seen enough myriads of them amongst the GEFS solutions!

Edited January 9, 2014 by Tamara תָּמָר

[ANYWEATHER]

I really don't know why people get hung up over a few model output scenarios because its not showing the cold coming up as it did a couple of days ago! Those folks who have been here long enough over the years know the twoing and throwing from the models predicting a cold spell is just normal. When as a cold spell predicted from the model output up toT+168 or longer ever been straightforward without any change in its output up to the T+168? period, Answer.....Never! Just look for trends, and the trend is still there for cold on the Gfs for instance but not so clear cut as some would like!  

[beng]

Okay, certainly a trend to increase the intensity of that low south of Greenland near 120hrs tonight from all models.

 

However ECMWF is not quite strong with this signal. Which is good, but certainly a move away from last night's excellent output,

but the better for cold prospects than the UKM & GFS

 

 

 

ECM is going more the GEM route IMO (fingers crossed anyway) with more of the energy held back west as the 2 lows phase, with a small amount of energy left to go East and under the block.  Don't want to temp fate here, but t144 could be cracking...

 

EDIT LOL t144 is very strange looking - not sure that's likely in reality.

Edited January 9, 2014 by beng

[Cecil Hogmanay Melchett]

ECM is better than the others at 120h.

But look at that big low south of Greenland at 120h,i have never in my life seen such an infuriating ammount of lows hurtling across the Atlantic over such a lengthly period of time.

[Tim Bland]

Are you sure Tim? There are only 4 members that briefly get below -6 850's as far as I can see. Central England.http://www.meteociel.fr/cartes_obs/gens_display.php?ext=1&x=255&y=82

-6c uppers are not required for snow if there is an easterly feed. -2c should do the trick. ECM looks good to me with -4c uppers and the low slipping under