Cheshire Freeze

Cold again...Certainly backs up what Fergie was saying the other day about the signal for a marked cold signature S UK into Jan. HP just to N and a cold easterly S of this. A point on the EPS discussion...haven't they been all over the place for the last 6 weeks or so? One moment looking promising in the extended range, the next flipping to something different?

Last 3 CFS runs for Jan Next one should be out in a couple of hours or so but fairly good continuity now....I'd like to see the height anomalies become a tad more striking but even so, I don't think we can discount some weak heights somewhere to the N of us through the month. The question is whether they'll be able to deflect the jet far enough S in our locale for us to benefit from them.

As long as we keep seeing bouts of amplification upstream (aided partially by huge Pacific ridge), we have a decent enough chance of getting enough ridging towards Greenland I have the distinct feeling it's a matter of when rather than if.

It's quite clear RE the Metoffice...as Fergie has said, there are a lack of clear cut background signals this year...they're all fairly neutral. Hence they have been relying solely on model output- model output which has either been swinging around or just plain wrong at times. I think that is why they appear to be changing direction a little more than they normally do.

Not as striking an anomaly as the previous run but it maintains the theme I take more notice when the CFS produces successive runs of the same general idea.

Looks like those crazy CFS runs you see at 700 hours + A real pipe freezer to end the GFS run this afternoon.

If it's a snowy set up you want to establish, it doesn't get much better than this

An improvement in the longer term though... Something is stirring... Cross polar ridging is a repeating theme...even if it is seemingly pushed back. Usually it means that there is a signal being picked up.

It's an evolving situation IMO. Heights could easily be sheared in towards Scandi from the collapsing ridge- something which won't be picked up properly for a couple of days yet. As the ridge collapses, watch the angle of advection on the western limb of the HP cell- the further towards N this points, the better as the HP will maintain latitude easier.

Great! Get your snow boots out then!

CFS remains steadfast on a blocked Jan.. SLP mean The notion of some Scandinavian height rises shouldn't be dismissed too hastily... Merry Christmas all!

That chart is GP's December thought a few weeks delayed. Troughing either side and a ridge straight through the middle.

I pay little attention to it...unless it churns out very similar output on consecutive runs...which it has done. Also it can't be that useless, it didn't back the potential for a colder Dec- unlike the others.

CFS seems to be picking up on something for January now too. A few runs in succession which have shown a similar trend

Haha Pacific ridge completes the hatchet job on the trop vortex deep in FI...if only!!

Wow, the 18z has been on the Christmas tipple... Best output of the evening at this point with heights building into Greenland.

First time I've seen proper 'potential' in the GEFS (in terms of cold uppers) this season. This is highlighted by the cluster of sub -5 uppers towards the end of the runs This is for NW England. Mean tanks towards -5 at the very end. I've been through the individual perts and a vast number of those -5 runs are cold zonality charts; mostly NW'lys to varying degrees. Little HLB on offer.

Indeed I am. Never pretended to be anything else. I have also been corrected on plenty of occasions... There is no high horse, just a desire for a touch of reality? I like a ramp as much as the next person but there is really nothing to even remotely raise a smile for at the minute- to suggest otherwise is just misleading. That's my point. There's a reason why even the rampiest of the rampers like Steve Murr are quiet at the moment...as he said earlier, we're looking 2nd week in Jan now at the earliest for a decent shot at cold.

There's potential at any given timeframe though. The day 10 ECM chart is the same chart we've been seeing day in and day out over the past 2 weeks or so. My point was why single that chart out and highlight potential? He was using that chart to make a point about the wider trend in the 14 day + period and he was wrong to do so because it does not fit that particular script. And neither should it do at day 10 (outside point of interest). People do have the right to post what they want...completely agree. However if you're going to post (an opinion as THAT ECM put it) then you leave yourself open to scrutiny if we're to have a healthy debate- especially when what you post is spurious in the first instance.

The Atlantic isn't blocked though? It's roaring away 500 miles N of us! We need to be on the N side of the jet, not stuck on its southern side under a dome of warm uppers!

No it's not harsh. It'd be nice if the point could be embellished as to where this 'potential' is being seen that is all. Iceberg is a long standing member of this forum so a little bit of realistic description as to where this potential is would be nice for the less learned surely?

I'm not moaning but it's misleading when people post a chart at day 10 and say 'this has potential'. It's even more annoying when said chart doesn't even show said potential.

The majority of the vortex is not on the Russian side at all. It's fairly central and directly over the pole. There is 0 of interest on that day 10 chart- a familiar tale of our HP not being able to gain enough latitude. All it's doing is stinking up the place time and again. That's exactly the same set up we've been in for weeks now with majority of jet going over the top of MLB.

Agreed. It is as far from a 'standard December' as you could wish to be (if you exclude the extremes a la 2015). 2C above average temperature anomaly is not typical in any month. I can't believe anyone would try and argue that this month has been standard!

We were in this position a week-ten days back though when in FI about 50% of the perts had some form of blocking or predisposition to blocking (at high latitude).