Model Output Discussion

[Coast]

Will it or won't it get colder according to the latest models?

Remember to keep on topic (Model Output) and enjoy some fascinating model runs!

[Bobby]

While the GFS op's insane easterly is an outlier there's a definite trend to bring something colder next week. GEM is good, ECM ensembles are good... so I get the feeling something is brewing.

[Ben_Cambs]

GFS 06z, Thurs 28th Jan:

8th Feb 91'

Feb 91 had a Scandi High, will GFS 06z shows the Siberian Hig. Also Someone could help me on this. Does the Feb 91 chart show the PV sat over Greenland, and not split into 2?

Edited January 19, 2010 by Snowman0697

[sandstorm2]

If you re looking for cold weather this mornings 0600 charts will bring a smile to the face, GFS brings frigid air over just about the whole country and so does the GEM at about +144, the ECM is not to shabby either at that range so there is obviously something afoot.

A Scandi HP cell of 1060mb is exceptional, but will it verify.

Isn't it amazing that the HP to the east of us just never gave up?

GFS 06z, Thurs 28th Jan:

8th Feb 91'

Don't really see any resemblance at all to 8th Feb 91.

SS2

[The Weather Dragon]

UKMO did lead the way with yesterdays 12z 144 Chart - The current 06z GFS pattern will become nailed in by Thursday with all models agreeing on an increasingley cold & wintry outlook. We are seeing the no-mans land uncertainty being replaced with a full on westward movement of the Siberian/scandi High. Expect retrogression of the high towards Greenland for early Feb

[Southender]

UKMO did lead the way with yesterdays 12z 144 Chart - The current 06z GFS pattern will become nailed in by Thursday with all models agreeing on an increasingley cold & wintry outlook. We are seeing the no-mans land uncertainty being replaced with a full on westward movement of the Siberian/scandi High. Expect retrogression of the high towards Greenland for early Feb

What makes you so sure JE?

The models are acting like a Mexican saloon door at the moment.

[cowdog]

While the GFS op's insane easterly is an outlier there's a definite trend to bring something colder next week. GEM is good, ECM ensembles are good... so I get the feeling something is brewing.

Its only really an outlier from about 150 hours on, until then its with the majority of the ensemble. Ok then it goes lets drop the 850 5-10 degrees in a day and is almost on its own, so very limited support for the extremes but the rest of the run does seem to support that its going to get cold, just maybe not national emergency level cold :lol:

[Ben_Cambs]

Oops misread your post, sorry.

SS2

No it was my fault for not mentioning the differences.

The GEFS ensembles are out and they look very good Fantastic!

http://www.meteociel...unpara=0&mode=0 (Longer Range)

http://www.meteociel...unpara=0&mode=1 (Shorter Range)

Edit: TEITS I hope you are here, I would love your view on this!

Edited January 19, 2010 by Snowman0697

[Frosty.]

UKMO did lead the way with yesterdays 12z 144 Chart

But today's ukmo 00z is disappointing at 144 hours so that is a concern for those who want an E'ly next week.

[The Weather Dragon]

What makes you so sure JE?

The models are acting like a Mexican saloon door at the moment.

Hi Shrimper

This is my own personal outlook based on a mixture of intense model evaluation, Global teleconnections & experience.

[sandstorm2]

Quite amazing outputs over the last few days, if these number crunching supercomputers can't come up with a solution maybe its time we all went back to sticking our finger to the wind, that didn't sound right but you know what I mean.

SS2

[The Weather Dragon]

No it was my fault for not mentioning the differences.

The GEFS ensembles are out and they look very good!

http://www.meteociel...unpara=0&mode=0 (Longer Range)

http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=6&runpara=0&mode=1 (Shorter Range)

UKMO will be back on board soon

[SP1986]

I'm not conviced about the GFS suggestion it looks very extreme when compared to other models. Again using the 2m temperatures shows you how extreme it is.. the ECM still in my opinion is the more realistic option, it's still cold no doubt but not to the severity of the GFS. I'm not convinced the signals point toward another cold spell more cold than that of before, it doesn't happen very often where there is a reload - we'll have to see what happens.

[kold weather]

With Europe as cold as it is further, esp further east in central/eastern parts, any SE/ESE airflow only will need a short amount of time to start brining in much colder air. Take a look at tomorrow and see just how weak the actual flow is and yet we still look likely to get some cold temps out of that, for once the SST's really shouldn't modify the flow too much at all...

As others have said I think the ECM is the most likely evolution BUT this set-up could very easily end up at the extrene end of the scale...on either side of the average...

[Thundery wintry showers]

UKMO did lead the way with yesterdays 12z 144 Chart - The current 06z GFS pattern will become nailed in by Thursday with all models agreeing on an increasingley cold & wintry outlook. We are seeing the no-mans land uncertainty being replaced with a full on westward movement of the Siberian/scandi High. Expect retrogression of the high towards Greenland for early Feb

That looks like a bit of a hopecast to me! The outlook is the same as yesterday- settled, probably cold to some degree, but detail hard to pin down. The GFS 06Z goes for the coldest and snowiest-case scenario.

[Guest North Sea Snow Convection]

I'm not conviced about the GFS suggestion it looks very extreme when compared to other models. Again using the 2m temperatures shows you how extreme it is.. the ECM still in my opinion is the more realistic option, it's still cold no doubt but not to the severity of the GFS. I'm not convinced the signals point toward another cold spell more cold than that of before, it doesn't happen very often where there is a reload - we'll have to see what happens.

As a well known snow fan I would agree with you Stephen. The GFS 06z has fairly cold ensembles but there is nothing there that suggests anything like the New Year cold spell. I would also agree about trusting the ECM more as well, rather than the usual gyrations and exaggerations of the GFS. Once again there are some fairly cold solutions in the ECM - but I think some forum members might be over anticipating the depth of the cold, much as they will be wanting it to happen, it isn't going to make it any more likely to happen.

The overrding message is that there is no continuity whatsoever within the models - so anything beyond the weekend needs to be treated with a lot of caution. Whatever either the operationals or the emsembles might suggest at this time.

ECM does look most realistic though I would agree. UKMO, whilst looking at odds with the other models, still shows the other extent of possibilities than can still happen too.

Edited January 19, 2010 by North Sea Snow Convection

[yamkin]

The ensembles are Look at what has snapped http://www.null/two/ensembles/

[The Weather Dragon]

That looks like a bit of a hopecast to me! The outlook is the same as yesterday- settled, probably cold to some degree, but detail hard to pin down. The GFS 06Z goes for the coldest and snowiest-case scenario.

No this isn't a hopecast. I am not saying that we will end up with what GFS 06z has suggested today, what I am saying is that a pattern is becoming established which will lead to an increasingly cold (not particularly severe) & wintry (not particularly snow) outlook.

[nick sussex]

That looks like a bit of a hopecast to me! The outlook is the same as yesterday- settled, probably cold to some degree, but detail hard to pin down. The GFS 06Z goes for the coldest and snowiest-case scenario.

I tend to agree TWS, the gfs 06hrs whilst great to look at is still not the most favoured outcome, it comes to something when i can't even trust its output at only 96hrs! Theres just too much uncertainty at the moment especially with the UKMO 00hrs run which looks very un-enthusiastic, i think high pressure closeby looks like a good call but to get to the gfs 06hrs requires alot to go right in the earlier stages, the way it halts the front sends the low nw at the same time developing a shortwave digging se'wards requires a leap of faith!

I will be very interested to see the UKMO further outlook today, just what will they come up with given the model uncertainty.

[kold weather]

One thing that does seem very likely looking at the ECM ensembles for De Blit is the very cold air will spread over to that location, whilst the ECM ensembles for the UK look far milder, stil cold but suggesting we end up under a HP cell rather then the beast thats over Europe.

However in this evolution we could still end up with surprisingly cold conditions, because that cold air is so close by, any drift from Europe is going to shunt our temps close to freezing, still early days yet however, eventual evolution maybe close to this set-up we have currently...

[Snowyowl9]

Going by GP`s forecast which has been very accurate,this is what he said would happen by the end of this month,a very cold january would be a major victory.

http://www.wzkarten.de/pics/Rgem2401.gif

And a mild february overall to come thats how I read it,cold at the very beginning of feb.

Even so great models runs today keeping the blocking going so at least it won`t be wet/windy,besides thursday night.

http://www.wzkarten.de/pics/Recm1201.gif

GFS shows the scandi high holding stronger today and also the 0z run,which gave a surprisingly cold easterly back.

http://91.121.93.17/pics/Rtavn1201.png

[yamkin]

I tend to agree TWS, the gfs 06hrs whilst great to look at is still not the most favoured outcome, it comes to something when i can't even trust its output at only 96hrs! Theres just too much uncertainty at the moment especially with the UKMO 00hrs run which looks very un-enthusiastic, i think high pressure closeby looks like a good call but to get to the gfs 06hrs requires alot to go right in the earlier stages, the way it halts the front sends the low nw at the same time developing a shortwave digging se'wards requires a leap of faith!

I will be very interested to see the UKMO further outlook today, just what will they come up with given the model uncertainty.

Am I right in saying that GEM 00Z started the colder trend followed by GFS 06Z? The reason I ask is because UKMO further outlook seems to be going along with the latest GEM & GFS model outputs.

[nick sussex]

Very interesting in that the UKMO further outlook have completely ditched the trend in the UKMO raw output and look to have gone with the ECM ensembles and dare I say it the trend of the GFS 06hrs run at least for the stalling front and this being pushed further west. However regardless of that outlook i would still have low confidence in anything past 96hrs and in terms of very cold and the propensity for models to make a complete mess of easterly type scenarios I wouldn't bank on this till within 72hrs, these stalling front scenarios and then being pushed west are a total nightmare to forecast!

[Guest North Sea Snow Convection]

I think that the METO update is much more in line with the ECM and its ensembles. They have covered the bases of some of that cold air over Europe perhaps getting into eastern areas during the first part of the week. The extent of the potential cold air westwards as suggested by GEM and GFS is not suggested to me by that update

I would agree with nick that anything beyond the weekend still has low confidence, irrespective of this update, which is quite different to yesterdays, and could still be quite different again as we go through this week.

Edited January 19, 2010 by North Sea Snow Convection

[nick sussex]

Am I right in saying that GEM 00Z started the colder trend followed by GFS 06Z? The reason I ask is because UKMO further outlook seems to be going along with the latest GEM & GFS model outputs.

The colder trend has developed over the last 36hrs especially with the ECM ensembles, its operational runs have also trended that way, the GEM has also picked up on this, the GFS has been a little up and down but overall has trended that way, it's still a problem though that the UKMO 00hrs has reverted back to its outlook of yesterdays 00hrs run, the problem for the UKMO is that they don't have their own ensembles but have to take into account the ECM, just because they generally disagree with the UKMO raw output doesn't mean the UKMO operational run is wrong, thats why until that comes on board i will have low confidence even in their further outlook today and certainly we can't ignore it, if it was a cannon fodder model i would happily dismiss it but its a very good model so i think people need to keep their expectations low until that moves towards the ECM and GFS.

Edited January 19, 2010 by nick sussex