Aye! Those were the days eh!

When I was a kid, a thick layer of snow was almost guaranteed at sometime during every winter and the

excitment of snow being forecast and the lampost light watching through the curtains waiting for just one flake to appear, not forgetting the

the smell, the aroma outside in the cold air of imminent snow...

Afaid now it has gone the same way as Christmas! No feelings about snow at all...

So far today I have been sitting back a bit, as I may be for much of the time 25th-26th depending on how the model output develops.

I see GFSP has shifted a long way toward the ECM/UKMO treatment of the weekend storm system but the motion continues to have too much of an eastward component to get the cold undercut that those two models have.

UKMO's output seems the most promising of the 00z runs, though ECM at day 6 has a very good dig of energy south in the Atlantic and was probably a whisker away from producing a decent continental feed days 7-10; the angle of the jet is just a little too much toward SW-NE.

The GFSP 06z is the most interesting run for a while as far as height rises to our E and NE are concerned, despite lower heights the NW than the ECM run. This is thanks to the jet alignment being just a little more toward S-N on day 6.

The day 8 chart screams 'battleground' but while the Atlantic low does disrupt days 9-10, it refuses to slide SE properly which makes a hash of things. Lower-res then ramps up the Atlantic, though we still see a heavily disrupted low days 11-12, angled SE-NW, which is quite a thing to see on the lower-res charts.

GFS continues to stubbornly pile energy NE which is what we're used to seeing from that model. Perhaps GFSP is showing us the benefits of the upgraded computation... it would be a good time to find out that it has a better clue when handling Scandi Height rises!

It's nice to be landing on familiar ground, with these potential easterlies infamous for teasing us with lengthy cold spells for days on end, with the end result depending on the Atlantic jet over the western half of the North Atlantic tracking far enough south to force the jet to either turn sharply north or continue travelling on underneath the blocking high.

For this purpose, the more low heights we can get down to the Med. this weekend, the better, as that will encourage the jet to power straight on under the blocking high.

Usually we end up with the jet splitting, the balance between the strength going over the block and the strength going under being the difference between a strong block at reasonably high latitude advecting cold east and a suppressed block at lower latitudes giving at best a 'continental whiff'.

For the best alignment of the easterly to get the properly cold air to the UK, a flat jet running underneath is best, unless low pressure development occurs due south of the UK i.e. somewhere from Spain to the Balearic Isles.

On the GFSP 06z there is only the merest hint of that split jet on day 7:

...which almost does the job for us during the following two days, but too much energy curves round to the north as the stronger jet arrives from the east, and curve this is unable to become sharp enough to permit a decent undercut of the Atlantic low pressure.

So as so often happens, we're seeking a reduction in energy going north/northeast, in favour of energy undercutting the blocking high.

These situations usually cause the models to struggle so it's not the best time to for it to turn up given the lower data counts that can be expected over Christmas 

Looking at some of the charts Gav has highlighted in his excellent videos , that looks unlikely

A little off topic, but did we not have an easterly a year or so back that was dry as a bone? I remember Gusty and a couple of others at odds with the Met's forecast of virtually no coastal snow showers, but it did end up being pretty much as forecast. 

Not off topic if you talking about the short lived  NE'ly, I'm not sure, might of been but would imagine that it was more of a case that you can never rule it totally out even if a slim chance for here in Kent with certain set-ups.

I remember when Steve had KWS he was the only one talking about a slim chance on some other event when the meto/beed wasn't having it, and guess what? we did wake to a dusting here in Kent 

Honestly cannot remember the specifics, other than the Met were saying it would be dry. Steve wasn't having it and said there was no way that setup wouldn't produce for Kent. It didn't and the rest is history. Again I can't remember the reason why it was bone dry across such a sea track. Steve will remember because he got a fair bit of unnecessary flack on Facebook over it. 

But that's what t*ssers do though aint it, remember the failed but never the correct...luckily it doesn't put most forecasters off having an opinion, sadly a few have gone because of that sort of thing.

Steve's hardly so precious about himself that he'd not laugh it off.

Exactly, anyone that get's into a hot tub to do a video forecast has to have some balls 

This is the 144 chart from the Chinese Model for 144 from the 0z run.  Cold Pc air continues afterwards as winds veer SE.

This, and he did.

Not hugely different to a few other NWP outcomes. The negative, obviously, are those lows sitting SW and NE of Iceland - both putting southwards pressure on the block.

For sustained cold, we really need to see the Jet either amplified (and us on the cold side of the flow; or driving right into the European mainland. Anywhere over the top of us and the block won't be stable enough to sustain itself (and would soon run out of very cold air to advect anyway)

Here is the 850 temp 168 chart and the accompanying SLP chart:

A taste of things to follow on the 12zs? Or just plain wrong?

This as a 168hrs offering from today's CFS.  Also shows a blocking high in situ.  Dry clear cold for many.

12z GME wants an easterly of sorts 

The "bomb" is no longer a bomb according to the GFS which makes the LP a lot less Low. at 75 hrs.

Wonder if this will have a negative impact on drawing in colder air -incase we get an easterly. This isnt out of character with the GFS recently - where LP's seem to back off the power in the final few days run in.

As a result we get to hang onto the midler air for a few more hours... yaaaaayyy

GFS is still barking (up the wrong tree)

Meanwhile here is the UKMO at t96:

Eye spy with my little eye...

something trying to form a greenland high?

LOL!

Not a half bad chart that

(is that trough disruption near the southern tip of Greenland??)

The 120 will be of interest...and here it is with the 850s...

Good atlantic trough disruption on UKMO.

GFS still crap.

Someone will have egg on their face