Cheshire Freeze

Looks like we've topped out at 2C today. Quite seasonal.

Got down to -3.2 with freezing fog last night. Everywhere coated white with a lovely thick hoar frost.

NAVGEM heading in ECM direction too...lol

Still, food for thought I suppose

Day 6 ECM though.... There is hope that it has picked up a new way forward...faint hope but hope nonetheless.

Right, that's it....I've decided- we're blatantly being trolled by the NWP

Thank you for this little snippet Ian.. It's quite unusual for longer range products to pull out marked -ve temperature anomalies at that range is it not? Certainly a better sign than what has gone previously (where the longer range output had no clear direction of travel for expected temperatures)

We've been hearing that the long range ECM modelling has been suggesting heights to the N and NW of the UK for about 3 weeks now. It has translated to absolutely zilch of note up to this point and medium range modelling & ensemble products take us through the first week of December with seemingly zilch on the table (from a deep cold POV). I'm certainly reigning in my enthusiasm for now .

I think GP has made his stance clear on numerous occasions...and it's one which involves a N European trough...

I don't know what there is to moan about...I appreciate that they give us little bits of insight like this. If they're prepared to take the risk that far ahead, it must be a measured one and I'll go along with it until it's proved to be a bust. If it turns out to be accurate then happy days

I can only assume that there are really quite strong signals for a -AO as we approach mid December. IIRC the Metoffice have traditionally done well with picking out cold spells when us amateurs couldn't necessarily see it yet. I recall them picking up on the January 2013 snow weeks before it hit...I know this because a council employee had been in work and told us that they'd been briefed. That was mid December I think. The Metoffice are not known for sticking their head above the parapet RE cold and snow unless they have some solid signals to suggest it.

John Hammond is a brilliant forecaster...one of the best the BBC have at the moment in my very honest opinion.

N'ly ready to blow?

The UKMO run is actually fairly decent going forward from day 6..compare it to the GEM and they're night and day upstream...with the UKMO being fairly amplified across Canada.

Couldn't make it up Bitterly cold air flooding in from the N/NE BUT we don't get a sufficient undercut

It has been on many occasion when aligned S-N rather than SW-NE. It pumps warm air into the higher latitudes and displaces cold elsewhere, often building heights as it does so.

Ties in well with the period that I think Ian mentioned the Metoffice were seeing a potentially more mobile spell??

Borderline how this plays out at day 10...could do with a smidgen more WAA a day or so before to really put a wedge between that Canadian troughing and the lower heights east of Greenland. However it plays out, there is more potential there at day 9 than there was on the 0z run so I'll take that positive and say 'thank you very much'.

Yeah, funny how models are so good at predicting zonality via an Atlantic onslaught. Can count down to it like clockwork most times.

The control makes it....

The mean is now on board with the extra WAA at day 8.. Also digs the LP to S of Greenland further SE. Encouraging at least- there will be some decent perturbations in this lot.

Divergence will be stark in this pattern because you either get sufficient WAA and a stronger block that sustains or you don't. It's as simple as that. Knife edge stuff but the direction of travel today has been good with that low exiting stateside being held back more and more each run.

Aye, here drops the trough from the NE

Highlights the differences between getting a good pulse of WAA northwards and not....Getting WAA north is important going forward into December...which is what I tried to point out last week when it was obvious the first attempt was failing.

Atlantic looks relatively blocked off chaps (at least northern arm of jet)...we may see the trough descend from the NE this run...perhaps interacting with LP to SW as per Metoffice long ranger?