Model output discussion - into the start of Winter

[Allseasons-Si]

The gfs 00z op and control at day ten,not bad that.

[carinthian]

10 hours ago, carinthian said:

If the forecast wave develops in the colder airmass out West of Ireland on Thursday into Friday as shown on the latest UKMO fax, the position of the low centre seems to be as shown on the ICON winter overview chart. Certainly a risk of snow , especially on the higher ground of the west and north. Of course these runs change daily but the risk is there.  Could be one to watch in an interesting weeks development to come.

C

Morning all , just an update follow on from yesterdays post. The ICON picture below towards the end of this week is similar profile to the UKMO run this morning. The low  centred further north than the GFS run, This position allows some wrap around of colder uppers on its western flank. So again a snow risk for mainly upland areas , especially  NW England and Wales going by this picture. See where ECM positions the low ? Meanwhile over here Fohn conditions expected later this week followed by a major snowfall on Sunday into Monday with the arrival of the cold front. Enjoy the weeks viewing back in blighty.

C

[That ECM]

10 minutes ago, carinthian said:

Morning all , just an update follow on from yesterdays post. The ICON picture below towards the end of this week is similar profile to the UKMO run this morning. The low  centred further north than the GFS run, This position allows some wrap around of colder uppers on its western flank. So again a snow risk for mainly upland areas , especially  NW England and Wales going by this picture. See where ECM positions the low ? Meanwhile over here Fohn conditions expected later this week followed by a major snowfall on Sunday into Monday with the arrival of the cold front. Enjoy the weeks viewing back in blighty.

C

Ecm. Similar story.

This might raise a few eye brows

Edited November 30, 2020 by That ECM

[SMU]

96 & 102 ECM

Edited November 30, 2020 by Steve Murr

[carinthian]

4 minutes ago, Steve Murr said:

96 & 102 ECM

ECM run showing more widespread snow with colder uppers deeper further south on this run. Still a lot to be decided yet even with-in the next 4 days but looking very interesting start to winter for you lot.

[That ECM]

Eyebrows going up and down and getting a right good workout this morning.

[West is Best]

With the North Sea still so warm I suspect anything off that ECM will be a disappointment except on high ground to the north. It's too early in the season and the upper air source would need to be far more penetrative.

I'm not meaning to be a killjoy. I can't see much excitement in this. It's going to feel cold but it's all a bit 'meh.' The GFS is trending away from cold and UKMO has now followed suit. And there's little in the GFS ensembles to make me sit up. Here's the 18z:

And the 0z:

 

The fact that UKMO has backed away from anything more sustained is not a good sign.

[northwestsnow]

Is that big low to west at day 8 going to disrupt?

[KTtom]

Each to their own and all that, but this for the western side of the uk is a pretty frustrating chart...what could have been a potent northerly wasted in the Atlantic, some were touting for the low to be further west, you got the direction wrong...also worth noting ECM was the first model to show the low blowing up like this a few days ago.

One change overnight seems to be the low drifting off east, cutting off any chance of influence from the Russian high, may not be a bad thing judging by the uppers associated with it! 

Edited November 30, 2020 by KTtom

[Kentspur]

Nice end to ECM with that low sinking south pulling a NEly in let's hope uppers improve 

Edited November 30, 2020 by Kentspur

[ItNeverSnowsInWindsor]

Looking great for Snowdonia this week with heavy snowfalls.

Not a bad start to December with the GEFS ensembles firmly showing below average temperatures for the first fortnight.

It's a game of patience to see more interesting synoptics appear with time but the main thing for now is the blocking.

Edited November 30, 2020 by prolongedSnowLover

[sheikhy]

35 minutes ago, Steve Murr said:

96 & 102 ECM

There you have it mate!!did say last night that the charts this morning might look better!!the chart abovecat just 4 days out

[mountain shadow]

Not a bad start to Winter.

Whilst there will be little low level snow for now at least it will be seasonal rather than ultra mild South Westerlies.

[Daniel*]

00z ECM much further east with the low several hundred miles and snow risk significantly more east I’m a bit doubtful of snow in SE the Chilterns very possible.

12z > 00z 

>

[SMU]

6 minutes ago, mountain shadow said:

Not a bad start to Winter.

Whilst there will be little low level snow for now at least it will be seasonal rather than ultra mild South Westerlies.

Yes > The day 10 ECM is cold with another Northerly push > potential reload again.

There hasnt been many Decembers since 2010 on ECM where its cold at 72 & stiol cold at 240...

 

[Mr Frost]

Morning all!

Models/charts still flapping about with regards to details/track Thursday/Friday/Saturday but to be expected at this range. 

UKM0 04/12 at 01:00

 

UKV 04/12 at 00:00 

 

UKMO 05/12 at 01:00

 

UKV 05/12 at 0:00 

As ever at this range...subject to change. 
Snow parameters combined for low ground are extremely marginal but you just never know! Could be rain, sleet or brief snowfall - high ground most at risk.

Just for fun the lying snow depth (mm) chart for the latest run - up to 05/12 at 03:00. 

 

Have a good day everyone! 

[bluearmy]

Can someone explain how Ukmo has ‘backed off’ from general guidance ???

[geordiekev]

Hello all, finally woke from my slumber thanks to my automatic alarm which wakes me on first use of the word Narnia or 20th use of the term Northern Hills.

So here we are and defo seems some promise. Let's not forget last years surprise Halloween dump in less than favourable conditions, but much like '18, early dumps seem to be Winter killers, so hopefully this years later start brings Eastern promise

Edited November 30, 2020 by geordiekev

[Paul_1978]

21 minutes ago, bluearmy said:

Can someone explain how Ukmo has ‘backed off’ from general guidance ???

I think he means you @West is Best

[Snow lover 2020]

21 minutes ago, bluearmy said:

Can someone explain how Ukmo has ‘backed off’ from general guidance ???

Is it just backing off for Christmas week or just this week? Blocking etc?

[bluearmy]

5 minutes ago, Snow lover 2020 said:

Is it just backing off for Christmas week or just this week? Blocking etc?

I assumed he meant Ukmo model rather than Exeter  .....l.after all, this is the MD thread 

[That ECM]

3 minutes ago, bluearmy said:

I assumed he meant Ukmo model rather than Exeter  .....l.after all, this is the MD thread 

Interesting disconnect between bbc and met for later in the week. ECM for BBC? 

[northwestsnow]

So the EC mean moving towards a collapsing Atlantic high longer term.

Hopefully the Euro low anomaly will assist us and stop a +NAO setting up...

Could be some cold frosty weather on offer further into December ...

[mb018538]

Mid to longer term clusters still look quite blocked, far from typical weather and our usual zonal Atlantic onslaught at this time of year! Certainly some potential routes to proper cold showing up.

[northwestsnow]

^^

Looks very blocked....