weatherguy

Well, technically, I suppose that's another way of getting a northerly... Let's hope the GFS is having a bit of a wobble before reverting to type re: amplification on its next run, rather than the surprising option of the UKMO actually coming out on top at +144.

Well, as Michael Scott once put it, "I'm ready to be hurt again"... Of course we know from our previous experiences that nothing is ever set in stone, but we can only assess what is in front of us. And that is broad support for an evolution, at a relatively close timeframe, which leads to some stonking charts.

And with that ~512 dam air...the instability...the possibilities! Absolute banker.

THAT ECM? No, THIS ECM. We've got 2/3 of the big hitters going for broadly the same evolution here, with the trigger occurring around +120h. And to be frank, if I was told that 1 of the "big 3" were showing a less promising set up, I'd be hoping to God that it was the UKMO at this sort of range. Game on.

Excellent chart, this, from the ECM at 216h. PV more or less completely drained from Canada. Does anyone else think a lot of the output just looks a bit...strange...thus far this year? Everything seems rather "flabby" and lacking in terms of isobar tightness. Typically I'd think along the lines of "oof, that HP over the atlantic looks transient with nothing really supporting it", yet there's no real pressure coming from the other side either!

Nothing much of interest for us coldies in the short term, the only thing on offer may be a transient northerly in the next 2 weeks as the atlantic begins to assert its influence into FI, such as the 336h GFS shown below. In my opinion, it seems like it's a case of watching how the stratospheric warming pans out (whether or not it will become a technical SSW is anyone's guess at this range!), and hope it delivers something big from mid-December onwards!

I'm surprised there's not more excitement over the 12z ECM's day 10 chart: A lovely Greenland high forming which looks like it would only grow in strength, the "UK low" remaining in situ to prevent it being flattened out, while the PV is coming roaring down from the Arctic...

I've had to retreat into the moans thread rather than seriously analyse the shambolic blob of HP to our east.... It's okay though guys, I've fixed it!

I almost typed something along these lines in my original post ha! I know how we can get "locked in" to zonal set ups, but sometimes it is necessary... A major issue from last winter if i recall correctly was that there were exceptionally warm SST anomalies in the Labrador sea which was powering the Atlantic blowtorch, detracting from otherwise favourable background signals. Looking now, we don't currently have the same extent of warm anomalies.

Indeed, I wouldn't quite call it game-over just yet (I am an eternal optimistic when it comes to chasing the white stuff!) but I'm not particularly optimistic WRT the current setup and how things have trended over the past 24 hours. I was hoping that we would see some stronger ridging in the Atlantic to make the most of the NH profile but, alas, this doesn't look likely now. I do think we need a period of progressive zonality to clear the board and establish a cold pool in a more favourable position, and hopefully we get some wave 2 action as we head into December so that we can capitalise. These stalling LPs aren't making life too pleasant in my part of the UK right now

Another time, we'd be looking at "snowmageddon" with the positioning of the Euro trough and the Scandi high - a damn shame about the placement of the Siberian cold pool! The +192h are akin to having the tap on your favourite barrel of ale being open, only to find there's nothing in said barrel apart from some rather miserable rainwater...

To offer a different view, would be that it is aiding the stasis of low heights in Southern Europe which is, in turn, likely to promote ridge-building in the Atlantic. It is however, like you say, blocking off a cold-feed from the usual Siberian cold pool. Best scenario from here would be LP remaining to our south, heights remaining robust to the west and driving more LP SSE across the UK for a period while that block is either forced back South, or pulled NW over time, with the cold pool being pulled around its flank. It's true though that if it stagnates, the UK will be left in a cold but wet situation. Seen far worse positions for the UK in November before though!

Phwoar. ECM at +240h is enough to bring me out of my Spring-Autumn sabbatical. Should the Scandy high hold in place for a few days from here on (which would be likely from here owing the Atlantic being shut off and LP moving SSE), there's some deep Siberian cold waiting to wrap around should the high become cut off. Flies in the face of the Nov EC seasonal update, mind, so we shall see.

If a series of charts could sum up winter... GFSP 240/264/348h Seemingly good NH profile, plenty of "potential" as an elongated high gets pushed to a NW and forces a negative tilt on western LPs....and...no slider, the thing collapses, and this "winter" goes on. ECM is no better as the 240h is as flat as the week-old lemonade in my fridge: Anyone fancy crowdfunding an attempt to dump a load of cold water into the Labrador sea?

Because it's the only way the GFS can ever be considered "top line" past +144h Excellent progress in the output as the zonal onslaught is at the very least abating in the medium term and with it come improved prospects for cold. Still very much a case of wait and see where the cards fall post-SSW though; would love to see the verification stats of the models historically through these events to highlight how much our old friend shannon entropy goes haywire throughout such period - experience tells us all that following anything other than trends is as enlightening as a mirror in a dark room... Stark differences at +240h, but enough to offer encouragement GFSP showing a blocked setup that with some adjustments could lead to retrogression up Greeny-way, ECM taking a slower route but is perhaps looking more favourable post day 10, while our *ahem* favourite model NAVGEM throws us a stonker at +180h. Meanwhile, the GFS/JEM/JMA didn't get the memo at all and show an atlantic profile flatter than that bottle of beer I just found left out from Christmas... Let's see where this takes us, but for now, savour this...

Can't really add too much that hasn't been explained brilliantly by Catacol. Just want to highlight this though; though the ops are pretty bland in nature out into FI, it's worth noting what is not forecast but is actually occurring NOW: The stratospheric vortex is taking an almighty beating as we speak...I mean, that above chart is a thing of beauty. Wherever we go from here, it will be fascinating seeing the response to this at the tropospheric level over the coming weeks...

With the wet air associated with PM/NW airflow, you'd typically need around -6 or -8c 850hpa temperatures to see snow anywhere other than on high ground. Unfortunately this chart would be miserable cold rain! 6z rolling out on the GFSP now, lets see if we get a more encouraging strat split on this run...

Chestnuts roasting on an open fire...

GFSP out to +96h now, quite remarkable how different it is to the GFS at such a short timescale.

Personally not a fan of these anomaly means in isolation, particularly in FI where the anomalies are watered down by law of averages. Were this to verify exactly as is, there would still be LP over greenland as the "average" is very low pressure, just minutely less. As such I only become interested in these where the anomaly is particularly great, which is very rare at this range.

Must be noted that despite the doom and gloom (understandable, given the eye candy we've been treated to in the past couple of weeks in FI), a mean never really getting above 0c at 850hpa still signals a largely blocked setup with no typically zonal weather for the time of year.

150h now....Slight variations to its last run, but much of the same theme - GFSP sticking to its guns.

Too early to tell, it's only out to +84h. 6z GFSP 12z GFSP

GFSP/GFS/ECM/UKMO +144h: Same again 48 hours later, excluding the UKMO as it doesn't run out this far, +192h: In essence, we have the ECM/GFS vs GFSP/UKMO. By +144h, the NH pattern for all is, as expected at this range, broadly similar. However, the 2 sets handle the Canadian sector with huge differences. In essence, the GFSP has the Canadian LP positioned far enough NE that it is able to influence the sciceland high, thus allowing the siberian PV segment to drop in behind. This is seen by +192, and the UKMO would perhaps progress to a similar scenario. For the GFS and ECM, this does not happen and in the prior the high melts away (worst case scenerio), while the ECM has the high go through a combination of retrogression and sinking, which does pull the high to a similar position as is seen in the GFSP, but prevents the siberian PV from dropping in around its back. Until the Canadian sector is resolved, the evolution of this scenario remains uncertain. All eyes should be looking west, not east, over the next few days to see how this progresses.

It will be interesting to see whether the GFS 18z's LP to our WSW at +216h will take a different orientation nearer to time. It really wouldn't take much of a correction to send more energy SE, cutting off the sceuro high and advecting that lovely siberian cold. We shall see, plenty to play for. In the meantime, enjoy some potential frosts and some snow showers next week for the lucky ones as the anticyclone takes hold. Certainly beats mild zonality!