Model Output Discussion - the cold has arrived

[swfc]

2 hours ago, bluearmy said:

If the NH profile is unusual then everything needs to be treated with caution imo. 

if you head back to 2010, I recall Stewart telling us that despite the nwp showing the demise of the greeny block, it woud not verify like that and within a few days, back it came on the extended ens …… one would hope that more than a decade on, the models would be better!  But they’ve proved over the past week that they probably aren’t …….

Det and op are the same 

Thanks BA, northwestsnow puts det looks good. Bit confusing snowing in Sheffield

[IDO]

The big three between D8-9 show that models are struggling late next week:

ECMGEMGFS

Just subtle differences earlier in the run around D5 with a wedge of heights pushing SE off the Greenland heights:

GEM is worse case, ECM best case, and GFS something in-between.

[markw2680]

1 minute ago, Kasim Awan said:

Possibility of big accumulations tomorrow night in parts of low lying NW England as an onshore wind develops streamer activity heading into a cold surface layer.

 

Iv got my eye on that too, just thinking there’s a chance it could push them into the midlands possibly 

[Rain All Night]

18 minutes ago, TSNWK said:

Anyone else watching the movement of purple vortex blob to our north east from around 144 

Can you imagine...

[MATTWOLVES 3]

It appears a little streamer got through around Sheffield...falling as snow but as rain back to Hull...you see folks these little features do pop up from time to time..I think perhaps lamppost watching at the ready this Weekend.

Snow for you lot up North can mean only one thing!............

Edited December 8, 2022 by MATTWOLVES

[Don]

4 hours ago, radiohead said:

Snow for pretty much everyone on the ECM tonight

Yes, not looking too shabby for my location either! 

Edited December 8, 2022 by Don

[blizzard81]

Ecm ens for debilt showing a few frigid easterlies from 20th Dec. I maintain we should be looking towards the scandi region for a height build up around that time. Latest gfs op is catching on to the idea too. 

[Premiere Neige]

12 minutes ago, The Enforcer said:

As of 22:20 there is the first significant incursion of precipitation into mainland England (Yorkshire/Nottinghamshire/Derbyshire):

What did the hi-res short-range models predict?

NMM T+10 - underplayed:

UKMO T+10 - non-existent:

Arpege T+10 - skirts the coast:

ICON T+4 - underplayed:

Conclusion: it doesn't matter if the models suggest it is going to remain dry.

I can confirm it is snowing in South Yorkshire just now...

[Eye to the sky]

1 hour ago, MATTWOLVES said:

Nice icon..Better corridor for Heights around Greenland...Nice build of heights East of scandi also..such a petty they only run it to day 5 at night..They must like to finish early

 

[bluearmy]

Gfs again finds a weak surface high to our east days 9/10/11

this feature does have a little more support today on the basis that the Atlantic trough heading ene could stall somewhat to our west and drive some WAA. Of course Scandinavia will also be v cold which could also encourage such a feature to establish 

 

[AltonMatthew]

I look at it like this, weve got the cold in place... Snow will come when it comes. I for one would just like the cold synopsis to continue to give us a more seasonal Christmas! If it snows great but cold and frosty this time of year is better than mild dross

[bluearmy]

There is currently no comparison with 2010 on depth of cold. The reason that 2010 crops up is the similarity of the broad sypnotic pattern in early December. 

Edited December 8, 2022 by Captain Shortwave
Removed now hidden quoted post

[The Enforcer]

10 minutes ago, Mapantz said:

UKV from yesterday:

 

Timings a little out, but pretty good on the precip distribution!

 

25 minutes ago, The Enforcer said:

As of 22:20 there is the first significant incursion of precipitation into mainland England (Yorkshire/Nottinghamshire/Derbyshire):

 

Gold star for UKV at T+28: only 4 hours too early.

Edited December 8, 2022 by The Enforcer

[Don]

What's crucial is we've actually got the cold in this time without it being cancelled at the last minute!  Plenty of snow chances to come at some point.

[Johnp]

Interesting that even when GFS tries to break the pattern down, not a single front can make it past the meridian. 

[IanT]

28 minutes ago, IDO said:

The big three between D8-9 show that models are struggling late next week:

ECMGEMGFS

Just subtle differences earlier in the run around D5 with a wedge of heights pushing SE off the Greenland heights:

GEM is worse case, ECM best case, and GFS something in-between.

….or, that the range of potential outcomes is still quite broad.

[Derecho]

18z ens looking a bit messy for the middle / later part of next week. The majority are cold with a northerly influence but a higher number of ens members compared to previous runs develop secondary features around that Azores low. 9 members have mild air making inroads, with some snow to rain events in places. Obviously northern areas would be favoured in such a scenario for something more prolonged snow-wise.

Quite a few more have a channel low too, is this Azores low saga still not finished? Probably an 18z wobble. Hopefully tomorrow can improve on that Greenland High signal!

Edited December 8, 2022 by Quicksilver1989

[Bats32]

Would be nice to get next week nailed down, then we can look further ahead. Still a bit messy.

[MATTWOLVES 3]

22 minutes ago, shawty1984 said:

But it happens every year, every cold spell and it needs to stop, it's ridiculous.

Can I just say one thing here before drawing a line under it. Firstly 2010 was a brute! Secondly we had that significant spell in place for the best part of 5 weeks..hence the fact it goes down as one of the coldest spells in many decades! And finally for some to even try and compare this cold spell which is merley 3 days in is futile and down right ridiculous! Yes it may end up not even coming close when all is Said  and done...but, and its a big but...if this spell were to continue for another 3 or 4 weeks then maybe we would be able to get close..but basically we need to reserve judgement until it runs its cause. But Hemispherical speaking there are definite similarities...we just need to see a greater depth of cold pooling...

Edit...BUT! I think I just set a record for the amount of buts I put in this post !

Edited December 8, 2022 by MATTWOLVES

[carled]

3 minutes ago, MATTWOLVES said:

..but basically we need to reserve judgement until it runs its cause. 

*course

[ICE COLD]

I wouldn’t have thought it would be long before we have anther go at a cold spell looking at the end of the gfs run . Definitely not a normal NH for the last third of December. Or we might just carry on with the one we’re currently in ? You never know

Edited December 8, 2022 by ICE COLD

[MATTWOLVES 3]

2 minutes ago, carled said:

*course

Predictive text and typing quickly I'm afraid! So very sorry!!

[damianslaw]

GFS continues to hint at my earlier predications for how the rest of the month pans out, at some point we will see a temporary easing of the cold thanks to warm air advection through the UK, atlantic trough to the west, but at the same time heights will be lurking to the east and a battle of sorts will take place between the atlantic and continental heights, possibly bringing something milder for all, snow to rain transition, but once the frontal activity moves through there is nothing behind it with the atlantic quiet and heights are then able to quickly build to the east, scandi high eventual outcome. Expect this messy transitional period to arrive before christmas, but not sure exactly when.

We shall see...

In the meantime, more of the same, could be a snowy surprise for the NW England tomorrow night into early Saturday morning, a very cold weekend ahead, freezing fog could be the biggest hazard. Much of next week remaining cold, northerly flow, chance of snow anywhere again, this quite possibly lingering through into the following weekend. 

[alexisj9]

2 hours ago, RainAllNight said:

Return to zonal flow confirmed, no height anomalies at all 

Lol no anomalies at all, think it's broken.  Must be lost.

[IanT]

Could parts of the SE see patches of freezing fog early Saturday and Sunday mornings..? On occasion this can be quite a (dangerous) spectacle.