Model Output Discussion - 8th December Onwards

[MR EXTREMES]

nope at t144 of the ecm it not a greeny high but pressure trying to edge west from scandi good heights if only the low pressure would sink but looks like wobbling about but will the strong heights to our east shear the 1050 scandi heights.

it does look to me that heights from the east is putting up a fight.

Edited December 9, 2012 by badboy657

[Davey80]

Why will it not just sink. It has nowhere to go further north

[cooling climate]

Looking at the t144 chart on wetterzentrale it just occured to me what a difference to

a forcast 400 or so miles further south would make and if that chart varifies then we would

be very unlucky what with the heights to the north and east.

[snowking]

Why will it not just sink. It has nowhere to go further north

Because unfortunately there is HP to our south over Iberia

Better run again though and once again a more increased risk of leading edge snowfall for many, Scotland looks to take an absolute battering.

Really the further south we can keep pushing this, the better - particularly for those folk down in the SW

SK

[MR EXTREMES]

held out in the alantic on the ecm t168 in other words its trying to fight back is it possible not sure because the other models dont support this outcome.

[TEITS]

Pretty clear to see what is happening between +96 & +168.

http://www.wetterzentrale.de/pics/Recm1681.gif

Slowly the Atlantic LP is weakening and the mega Russian HP is slowly backing W.

[BurwellWeatherWatch]

held out in the alantic on the ecm t168 in other words its trying to fight back is it possible not sure because the other models dont support this outcome.

The fact that ECM shows it as a possibility tonight, means it is just that. The sheer number of possibilities being ping-ponged around the models in the last 24-48 hrs is really baffling and does show just how the UK's weather can range anywhere between 2 extremes with only the most finely nuanced adjustments on the global scale.

So don't believe anyone who pronounces the next week with 'high confidence'. It really is open to any eventuality, though it's clearly odds-on for the Atlantic to make some kind of incursion, however small or large. To what extent is the big question. Great to see the model thread a bit calmer today, and some posters who have previously shown the most entrenched bias, acknowledging the range of options on the table by next weekend. In a funny kind of way I feel a bit more relaxed now the mega-E'ly has been downgraded and can just sit back and enjoy what is unfolding. December is far from written-off!

[Davey80]

Because unfortunately there is HP to our south over Iberia

Better run again though and once again a more increased risk of leading edge snowfall for many, Scotland looks to take an absolute battering.

Really the further south we can keep pushing this, the better - particularly for those folk down in the SW

SK

Where's the southern arm of the jet? Is it too far south?

[Eskimo]

Pretty clear to see what is happening between +96 & +168.

http://www.wetterzen...cs/Recm1681.gif

Slowly the Atlantic LP is weakening and the mega Russian HP is slowly backing W.

All I can see on that chart is the spitting image of all our faces during this volatile state of model watching.

[stevofunnelcl]

Is the snowy breakdown all over? Is the super undercut (with us on the cold side) a possibility? Who knows. There's about 650 miles in it!!!

Friday looks unpleasant, strong south-east winds, possible blizzards for Highlands

Deep low - 965

Wet and windy. Worried that flood problems will be returning

Edited December 9, 2012 by stevofunnelcl

[cooling climate]

T168 and the low is being dragged back by the low behind it I think and the orientation

of the high to the east could be very interesting final three frames of the run.

[cold snap]

I smell a easterly coming at the end of this run

The low is sent packing back where it came from

Edited December 9, 2012 by cold snap

[nick sussex]

The jump from 168hrs to 192hrs on the ECM looks very suspicious.

I really don't see how it manages to eject that low so quickly se'wards. Very strange and not convinced by its synoptic evolution.

[MR EXTREMES]

no easterly at t192 mind u fi but cool se flow grrrr its not happening grrrr

[chris55]

I'm liking ECM tonight. The Russin high is (unusually in this situation) ridging Westward with the associated cold uppers under it's southern flank. The Atlantic is disrupting and basically losing the fight. At the moment there is not much interest for our patch but with such a set-up we could well see changes. Just look how the models have been chopping and changing at T72/96/120 with such a set up in the shorter term.

http://www.wetterzen...cs/Recm1921.gif

The jump from 168hrs to 192hrs on the ECM looks very suspicious.

I really don't see how it manages to eject that low so quickly se'wards. Very strange and not convinced by its synoptic evolution.

Surely it just disrupts against the might of the Russian high?

Edited December 9, 2012 by chris55

[Jason M]

In terms of the current cold spell, I think the message tonight is that that ship has sailed. The Atlantic will almost certainly break through in my opinion, although the weather can't be described as zonal even if conditions on the ground suggest otherwise. Every model and every ensemble points to this.

Next weekend and beyond is anyone's guess as everything hinges on whether the energy undercuts to our south or more likely in my view decays gradually in situ. If it undercuts we win, if it decays its impossible to predict where we will end up.

One thing is for sure though, there will be a lot of rain in the SW and a lot of snow over high ground in the north and Scotland.

Jason

[mulzy]

"The winter killer" aka the Azores High showing its ugly face on the ECM 192.

[latitude]

Pretty clear to see what is happening between +96 & +168.

http://www.wetterzen...cs/Recm1681.gif

Slowly the Atlantic LP is weakening and the mega Russian HP is slowly backing W.

Can you just explain the consequences of that a little more for a newbie perspective. Thanks.

Its amazing, dosent really feel like a cold spell one bit next week, except for the usual winter frozen car in the morning!

Edited December 9, 2012 by latitude

[IDO]

Wow ECM from T216 (obvious FI):

Feed of very mild air heading our way.

[nick sussex]

I'm liking ECM tonight. The Russin high is (unusually in this situation) ridging Westward with the associated cold uppers under it's southern flank. The Atlantic is disrupting and basically losing the fight. At the moment there is not much interest for our patch but with such a set-up we could well see changes. Just look how the models have been chopping and changing at T72/96/120 with such a set up in the shorter term.

http://www.wetterzen...cs/Recm1921.gif

Surely it just disrupts against the might of the Russian high?

The might of the Russian high even if it was on steroids wouldn't manage that, its actually bulleted that low se into Italy quicker than the rush to the doors at the Harrods sale!

And as we see later the Russian high teases and then wants to go home. Generally in this set up if its going to happen the models will deliver it quickly as the PV forces some westwards retrogression as it heads to Siberia.

I have a rule for these Russian highs, three strikes and you're out, basically we see many of these modelled which hang around never quite make it and then head away.

So if its going to happen the models will go to that solution quickly, give it a few days and lets see whether we see some retrogression in the pattern.

Edited December 9, 2012 by nick sussex

[phil nw.]

The 12z runs all bring the Atlantic in by the weekend after some front edge snow for the north.

I can`t see much change now at this range to the general pattern,disappointing as it is for cold/snow lovers.

The heights to our north just too weak and the stronger Siberian block is too far east.

http://www.meteociel...CH1-96.GIF?09-0

http://www.meteociel...96-21.GIF?09-18

http://modeles.meteo...snh-0-96.png?12

The resultant pattern is to allow that east-west trough disruption across our latitude and this unfortunately could well be the outlook for a while until heights decide to rebuild further west.

The gefs tell the story at T192 most go for a trough near the UK at that stage as indicated by the mean

http://176.31.229.22...nh-21-1-192.png

http://www.meteociel...&mode=6&ech=192

and the London ens graph

http://modeles.meteo...ndres&runpara=0

a reasonably tight bunch for something of a "warm up" towards average after the breakdown.

[snowking]

Consistency from the later ECMWF output but with a large westwards step

12z Yesterday:

And today:

And even in the earlier timeframe:

Yesterday:

Today:

Even compared to two days ago:

So todays trend is very much a positive one....whether that continues into the 0z's well nobody can say

SK

[chris55]

"The winter killer" aka the Azores High showing its ugly face on the ECM 192.

It's only a winter killer when it set's up with a strong Polar Vortex to the North. ECM 192 couldn't be further from a "winter killer" if it tried.

[Just Before Dawn]

It's like watching two punch-drunk 50 year old boxers swinging and missing.

[Froze were the Days]

Personally we're not really getting anywhere at present with the ECM and today's output in my mind is very similar to yesterdays the difference being the decaying Atlantic LP as it tracks back west is only replaced by another similar synoptical low pressure and this time probably more of an easterly progress against the Russian block, this could go on for some time and might take a further third low to displace the block and errosion into Europe - that's how I read it.