Model output discussion - deep cold inbound?

[kold weather]

Yeah I don't think anyone wants the GFS compared to the GEM 12z run. That run gives several snow events working progresively further north.

Much better than the way the GFS deals with it which is to lift the whole complex up from the other side of the Atlantic. If we can get that LP closer that will give us more room for error.

[Timmytour]

3 minutes ago, Tim M said:

Genuine question from a lurker with little knowledge but a strong interest... If, as everyone is saying/implying, the GFS is such a poor model for so many situations  (blowing up lows, too progressive with westerlies breaking through blocks etc), why are we all scrutinising it so much and so often so many times every day?   If the UKMO is really king surely that is all we should be concerned with?

More runs, 6 hour timeframes and running out to well past 10 days means it gets subject to a lot more scrutiny imo.   

To be honest my first recollection of seeing the potential of this weekend coming was on the GFS.. It modelled it relatively well until ironically the ECM finally got on board! 

[Djdazzle]

We have seen easterlies crumble at T72 . . .

But I don't think this will be one of those occasions. Looks like GFS has gone off one one.

If the ECM shows the same, I may start to get a little concerned.

[supernova]

GEM is magnificent. GFS isn't.

UKMO is magnificent. GFS isn't.

UKMO freezes the entire country in  -8 to -10 uppers until the end of the run and then looks set to slide the upstream low. GFS doesn't.

GEM picks up intense streamers and delivers significant snow not just in the east but right across to the west of the country in many areas before a major snow event next weekend which could be temporarily marginal for the southern-most counties but too far out to even bother speculating.  GFS doesn't (too progressive as always).

ECM will hopefully follow the UKMO/GEM later. GFS probably won't. And even if it does I still won't care.

GEM streamers and snow event.

GFS Op significantly above the mean as it tries to break down the cold progressively. Might be right. Probably isn't.

 

 

Edited February 4, 2021 by supernova

[Kasim Awan]

Just now, supernova said:

GEM is magnificent. GFS isn't.

UKMO is magnificent. GFS isn't.

UKMO freezes the entire country in  -8 to -10 uppers until the end of the run and then looks set to slide the upstream low. GFS doesn't.

GEM picks up intense streamers and delivers significant snow not just in the east but right across to the west of the country in many areas before a major snow event next weekend which could be temporarily marginal for the southern-most counties but too far out to even bother speculating.  GFS doesn't (too progressive as always).

ECM will hopefully follow the UKMO/GEM later. GFS probably won't. And even if it does I still won't care.

GEM streamers and snow event.

GFS Op significantly above the mean as it tries to breakdown the cold progressively. Might be right. Probably isn't.

 

 

I'd argue all output is magnificent relative to the last few years worth.

[nick sussex]

1 minute ago, kold weather said:

Yeah I don't think anyone wants the GFS compared to the GEM 12z run. That run gives several snow events working progresively further north.

Much better than the way the GFS deals with it which is to lift the whole complex up from the other side of the Atlantic. If we can get that LP closer that will give us more room for error.

KW have you had a look at the GFS 0.25 view .

What do you think . It’s making a meal of that shortwave in the Channel.

[Weathizard]

2 minutes ago, Tim Bland said:

I said Borderline ...at the end there are only a couple (out of 34) as mild ...

I guess, I’m probably just being facetious just when I see the term Outlier I think something that’s totally out of sync with the rest of the suite. Certainly towards the top end, those ensembles are basically about as useful as a chocolate fireguard anyway. 

[Methuselah]

7 minutes ago, Djdazzle said:

We have seen easterlies crumble at T72 . . .

But I don't think this will be one of those occasions. Looks like GFS has gone off one one.

If the ECM shows the same, I may start to get a little concerned.

Aye, and I can still recall several such occasions, from the 1960s. Just because the zeitgeist implies cold, it doesn't  mean that cold is 'nailed on'. Although, in this case, I suspect (HOPE) that it is!

Edited February 4, 2021 by General Cluster

[Kentspur]

34 minutes ago, Mike Poole said:

GEM gets off to a very good start at T96:

-16C line not that far away, really!

Perhaps GFS meant to put colder uppers rather than milder uppers over Kent -12c there over East Kent!

[nick sussex]

Just now, That ECM said:

Three course with seconds.

I’m calling it the hump of doom . The others have that clean flow , you can see that hump sitting in the Channel where the shortwave energy is .

[Keefo]

GFS 12z only one run. There will be no doubt subtle changes in either direction between now and the weekend. Keeping us all occupied though!!!

[Devondelight]

What time should we expect the ECM? 

[Frosty.]

Very pleased with the Gem 12z op, keeps most of the u k locked in the entrenched cold / very cold pool with plenty of snow around too...fingers crossed our upcoming bitterly cold spell will last right through next week!..and beyond!  ️..I’m really excited about this spell..yes spell..not a pathetic blink or miss it snap..the models are trying to prolong it with lows on more of a southerly track with heights maintained to the north...anyway, that’s enough waffle from me...I’m going to go stock up for the imminent FREEZE!

[Weather-history]

38 minutes ago, nick sussex said:

GFS 12 hrs run = Butlins .

UKMO 12 hrs run = The Dorchester .

That might sound brutal but it’s not just the less cold uppers but the quicker breakdown .

Don't you mean GFS is

[Snowman.]

GEFS Ensembles are starting to look interesting.

More proloning the cold with a wedge to the N keeping the Easterly flow going well in D8-9.

[MJB]

9 minutes ago, Tim Bland said:

Day 10 on the GEM and most of the us is buried, still under cold air and still some snow around. Hope ECM follows suit! 

Gem really was a Gem , excellent run

[tight isobar]

I-cannot emphasise enough that diverge >model mismanagement will be fraught until the surface has encoded the circulation... panic about overheads will be relieved when the flow entails... and as the ecm will likely already alternate this evening.. as when on the cusp it’s the queen at dealing with such features/scenarios... also lastly for now... the shock of such great evolutions = Synoptics are only just beginning... when this flow engages... I think the anti will only ......UP!

Edited February 4, 2021 by tight isobar

[Notty]

10 minutes ago, Djdazzle said:

We have seen easterlies crumble at T72 . . .

But I don't think this will be one of those occasions. Looks like GFS has gone off one one.

If the ECM shows the same, I may start to get a little concerned.

If the ECM shows the same I'm starting on the wine early tonight !

[sheikhy]

Another thing to note is the ukmo and ecm have a bit more amplification around eastern states at 144 hours which helps disrupt the trough a bit more!!the gfs is much flatter for the same time period!!

[Speedbird]

4 minutes ago, haywood1982 said:

What time should we expect the ECM? 

from 6pm

[Man With Beard]

Updated my forecast from yesterday based on last 24 hours of runs. Taken into account small shifts on ECM and GFS in the nearer timeframe, with a wider area of snow possible on Sunday - decided not to be swayed by the GFS's very progressive take on the midweek front...

 

[Weather vane]

17 minutes ago, Tim M said:

Genuine question from a lurker with little knowledge but a strong interest... If, as everyone is saying/implying, the GFS is such a poor model for so many situations  (blowing up lows, too progressive with westerlies breaking through blocks etc), why are we all scrutinising it so much and so often so many times every day?   If the UKMO is really king surely that is all we should be concerned with?

Valid point. In fairness to the GFS, it was very early to signaling this easterly, so must get points for that. Sure, it has a habit of being over progressive on the atlantic lows, but even if that's the case at this moment, there is still the very real threat of the atlantic cutting off the cold air for most from days 8-9. But let's not worry about that yet, and enjoy what's coming up !

[tight isobar]

1 minute ago, Man Without Beard said:

Updated my forecast from yesterday based on last 24 hours of runs. Taken into account small shifts on ECM and GFS in the nearer timeframe, with a wider area of snow possible on Sunday - decided not to be swayed by the GFS's very progressive take on the midweek front...

 

Mwb:we know the gfs crave for mobile conveniences..and fold and revert... again as per last post.. when the easterly engages at the surface... the models will reflect....

[Snowman.]

Quick! someone post the CFS before everyone loses there mind!

Edited February 4, 2021 by Snowman.

[ptow]

7 minutes ago, MJB said:

Gem really was a Gem , excellent run

Only 0.5 to 1cm for most of the South on that run, but yes good for cold