Model Output Discussion - moving into Winter

[mbrothers]

13 minutes ago, LightningLover said:

Hmm, ECM 00zis a bit squeaky bum time for us southerners...  (I adore that phrase haha!) I pray it's a wobble!

Are u saying it’s a wobbly squeaky bum?

[sheikhy]

1 minute ago, mulzy said:

The blowing up the low to the SW is probably on the extremities of the envelope.  Fine margins here and there.  The initial attack from the north east is slightly too far west.

Did the same thing yesterday but then took it slightly east 12z!!if you take out the last 2 frames of ecm then this realky is a barnstormer of a morning for coldies on here!!gfs is an upgrade and clearly ukmo is a beauty aswell and that damn iby low seems to given up goin north finally!!now we await with interest whether that little bump to the north east takes things too far west or will it flatten slightly and give us a direct hit!!we should be home and dry by the evening!!

[Ali1977]

Apols for the morning ramps, I’m just happy to be in the reliable now - once it’s here it doesn’t look like going. I think the Twitter forecasters will be ramping it too today !! Expect a METO wording change . 

Edited December 2, 2022 by Ali1977

[seb]

And once again, a perfectly normal model wobble-about of 200 miles at 9 days from now is causing doom and panic.

Please look at the big picture. Please remember how much models struggle in this kind of setup.

The overall setup has not changed, it remains brilliant and extraordinary for early December.

Edited December 2, 2022 by seb

[Met4Cast]

It's certainly a change of direction on the runs but not necessarily a bad one, just different from the cleaner north-easterly we had been seeing. Interestingly the surface Scandi high that Crewe mentioned is now appearing on the GEFS mean.

I'm not sure - I like to see consistency between runs across models and we haven't really got that at the moment, but neither are we seeing consistency for mild weather, it's mostly cold just the route getting there is perhaps changing a little. Good runs this morning.

[Chesil View]

I would imagine the Ecm run in it's latter stages  is right at the edge of the envelope pressure wise for the south of the UK. A channel runner or slider will be in that envelope somewhere as well.

[nick sussex]

What drama !

The ECM blows up the low to the sw which moves ene . Not enough forcing because of too much height seepage west so you don’t get sufficient trough disruption .

This all stems from the block being too far west initially . The original trend of having a more Omega type block seems to have disappeared and so now it becomes very complicated .

Theres likely to be some decent snow for parts of the UK . At the moment northern areas look best placed .

If you’re in the south you need a correction se of the pattern and more trough disruption to sheer that energy along the Channel .

Its all very finely balanced and a pattern that at the moment has little margin for error . 

 

[Lukesluckybunch]

I think the crucial..time frame at the moment is between 120-168 with the importance of where that trough drops it seems to want to drop over us..then move southwest..we need it to move South and more importantly eastwards..I think this has a chance of going very wrong..just my opinion..I do hope I am so wrong..in my.opinion that ecm run never got going.

Edited December 2, 2022 by Lukesluckybunch
Spelling

[TSNWK]

6 minutes ago, mulzy said:

The blowing up the low to the SW is probably on the extremities of the envelope.  Fine margins here and there.  The initial attack from the north east is slightly too far west.

The initial attack from the north east is now within 144 so reasonable confidence so it being a bit too far north and west is realistic

[January Snowstorm]

The Greenland high looks less robust this morning long term. In turn the Atlantic jet has really kicked off to our far Southwest. In reality what this means is a chance of copious amounts of snow but also brings the word marginal back in the frame.

For me I preferred last nights run where the depth of cold was stronger but likely much drier. The ECM is great as is, but very very close to it all going wrong!

[mb018538]

Just now, January Snowstorm said:

The Greenland high looks less robust this morning long term. In turn the Atlantic jet has really kicked off to our far Southwest. In reality what this means is a chance of copious amounts of snow but also brings the word marginal back in the frame.

For me I preferred last nights run where the depth of cold was stronger but likely much drier. The ECM is great as is, but very very close to it all going wrong!

Usually the case here. Colder and drier or marginal and more snow, but the cold disappears. Looks to me that those deep lows around the SW will ruin everything as usual.

[sheikhy]

1 minute ago, nick sussex said:

What drama !

The ECM blows up the low to the sw which moves ene . Not enough forcing because of too much height seepage west so you don’t get sufficient trough disruption .

This all stems from the block being too far west initially . The original trend of having a more Omega type block seems to have disappeared and so now it becomes very complicated .

Theres likely to be some decent snow for parts of the UK . At the moment northern areas look best placed .

If you’re in the south you need a correction se of the pattern and more trough disruption to sheer that energy along the Channel .

Its all very finely balanced and a pattern that at the moment has little margin for error . 

 

It will happen nick it will happen dont worry!no drama yet lol!!looking brilliant this morning!!!!im sure it will correct east slightly!!!

[weatherguy]

Gentle reminder that after an initial blast of cold uppers from the Ne/E, it’s inevitable that there’ll be a mixing out of these to some extent when milder/wetter Atlantic air comes in.  But, this isn’t a bad thing assuming we maintain low dew points (which we do, when LP systems are to the south) - you don’t need brutally cold uppers in such a setup.  More eye candy this morning!

[Met4Cast]

Wow..

The mean is essentially below -5c throughout the entire run, that's an incredible set of ensembles. The "milder blip" is much shorter too.

[nick sussex]

Just now, Lukesluckybunch said:

I think the crucial..time frame at the moment is between 120-168 with the importance of where that trough drops it seems to want to drop over us..then move southwest..we need it to move South and more importantly eastwards..I think this has a chance of going very wrong..just my opinion..I do hope I am so wrong

You’re not wrong . I’ve seen these set ups over the years and they do have high risk v high reward.

Its really the block seepage which causes the initial problems . The more boxed in the high the better .

 

[The Northern Ramper]

13 minutes ago, Ali1977 said:

Snow storm as I mentioned

Bank bank bank bank

[Tim Bland]

17 minutes ago, Ali1977 said:

Snow storm as I mentioned

Looks short lived though and turns back to rain away from highest hills and mountains. Need this pattern to shift south or to disrupt along the Chanel  for it to stay as snow 

[Scott Ingham]

10 minutes ago, Lukesluckybunch said:

I think the crucial..time frame at the moment is between 120-168 with the importance of where that trough drops it seems to want to drop over us..then move southwest..we need it to move South and more importantly eastwards..I think this has a chance of going very wrong..just my opinion..I do hope I am so wrong..in my.opinion that ecm run never got going.

The run is very cold snowy all the way through for northern areas and for several days in the south. No point in worrying about the placement of a low pressure system at t-240. The general pattern and height rises over greenland are pretty much set in stone i think your over worrying and thinking

[Frigid]

I've never seen ensembles this cold and prolonged in early December. You normally get lucky to see the mean fall below for a few days,, not till mid month 

[Lukesluckybunch]

23 minutes ago, Scott Ingham said:

Between 144 and 168 snow is popping up all over the show with them heights 850s and slack nature of the air. Theres nothing wrong with this run

Yes it might be..But as I said I think things are kind of on a knife edge,maybe I am wrong here

[Cymro]

22 minutes ago, Lukesluckybunch said:

I'm starting to get a bad feeling about all this..even at 144-168 it appears most of the cold air spreads west to the northwest of the uk..we need a eastwards shift here..and the whole system needs to be further South

I understand nerves but if you can't find positive outcomes with this current almost historical output I'm afraid you simply won't ever be satisfied. I've been a member of these forums for nearly 15 years and this is absolutely one of the most exciting build ups to a cold spell I've ever witnessed and I was here in 2010!! 

[IDO]

The ECM looked great at D6:

With a chunk of cold incoming to reinforce the pattern and help sustain the GH. The spoiler Atlantic low arriving too early spoils that scenario:

All that cold getting parked in Scandi whilst the low crosses. Clearly we just need a few changes to get that to be a much better prognosis in the D9-11 period. So all to play for at this range. 

Edited December 2, 2022 by IDO
Missed space

[Vikos]

all these perseverance slogans are well and good, but I get the feeling that the potential is not being exhausted.  this western shift is probably the logical solution with a relatively southern 552 line

[Lukesluckybunch]

9 minutes ago, Scott Ingham said:

The run is very cold snowy all the way through for northern areas and for several days in the south. No point in worrying about the placement of a low pressure system at t-240. The general pattern and height rises over greenland are pretty much set in stone i think your over worrying and thinking

Ok but would you agree with me that a shift South and east with the pattern would benefit us..I'm just thinking of the whole pattern is too far South and west,we will get a wrap around from the med?..maybe I am just searching for the absolute perfect output haha

Edited December 2, 2022 by Lukesluckybunch
adding

[SLEETY]

Ecm will be a big outlier on the pressure maps I would think.