General Model Output Discussion Tuesday December 22Nd:

[David-kig]

on the gfs 12 it really doesn't get mild any of the uk apart from far south west. overall 6-7 is still abit below average in the south and it has to be said it looks as though it will get colder again!! intresting time ahead. nearly 2 weeks of below average tempertures now. can't go wrong with that

[Upgrade]

Not much has been made of the Aberdeenshire Blizzards unsurprisingly as everything centres on southern and southeast england re media attention etc. You are right though, the cold air will probably stick up there and then be reinforced by another cold surge later in the weekend and more especially during next week, 12z runs so far suggesting another very wintry spell next week which could continue to reload as the gfs 12z suggests, I preferred the 6z though.

Slowly but surely it is starting to turn into a really decent winter for snow lovers, in many parts of the country.

The latest charts are surprising because many had expected mild to win out - the pub run is awaited with baited breath!

[Tucco]

UKMO 12 z fax's

http://www.wetterzentrale.de/pics/brack0.gif

http://www.wetterzentrale.de/pics/brack0a.gif

http://www.wetterzentrale.de/pics/brack1.gif

http://www.wetterzentrale.de/pics/brack1a.gif

Actually might get some decent snowfall here at last from that, more in line GFS 12z

xmas day, increased blocking

http://www.wetterzentrale.de/pics/brack2.gif

00z fax for xmas day.

http://www.wetterzentrale.de/pics/brack2a.gif

Mark

Teesdale,Co Durham

[D KARLSON]

as some rightly point out there not much point talkin about it when your to busy looking at it !!!

As for charts i feel the old fashoned methods are useful here what the synoptics infer are not necessarily what the weather is at ground level , we are in one of those situations, now cold air is entrenched and mild air rides over the top as opposed to pushing the cold air away , in fact it takes several attempts to push heavy and dense cold air at the surface out of the way.

I must say im not too surprised at the charts backing away from mild as any mild air that did make its way in ,would have its effects diluted by surface cold.

Inference for a few days ahead is difficult best just stick to 2 days , but that said a definite theme is emerging

and that is one of outbreaks of snow just about anywhere ,but more especially northern england scotland .but that

does not rule out surprise snowfalls in the south with temps marginal and sometimes on the right side of !!!

looking further ahead its quite possible the very cold air that stays in situe over scandinavia will make a comeback

after xmas.

so to sum up a very exciting prospect ahead watch carefully each forecast on the BEEB for snow in your area ,weater radar and temp, i feel theres going to be some fun and games with these synoptics some places could get anther pasting ; enjoy

[ISAAC]

Latest GFS run is on wrong side of marginal for tommrow night hence a washout for many areas... say good bye to the snow cover

[nick sussex]

Ecm jumps on board the train to yet more cold and snow with filling low to the south and possibilities of some major snow, just too far out to be certain here but the trend this evening is towards continuing cold in the outlook.

[Guest North Sea Snow Convection]

Really liking the ECM 12z - two undercutting lows from t144 to t192. Cold air getting right back down across the whole of the UK. More snow to be had with a nice NE atlantic ridge

Edited December 22, 2009 by North Sea Snow Convection

[nick sussex]

Really liking the ECM 12z - two undercutting lows from t144 to t192. Cold air getting right back down across the whole of the UK. More snow to be had with a nice NE atlantic ridge

Evening Tamara i agree the ecm is looking really good and the three major models agree on the trend. It's funny in any other winter these synoptics would have led to this thread imploding with excitement, for the moment people are just immersed in the current cold spell and perhaps are forgetting how difficult it has been in recent winters to sustain any cold spells that also give snow chances throughout their duration.

[snowlover2009]

ecm is brilliant, unbelievable the amount of snow this area could get. we have snow cover since thursday and then comes this mild blip. MIld blip lol? then we are snow bound once again some significant snow for much of england and wales on ecm tonight

[TEITS]

Certainly an interesting trend from the models just after xmas. If I had one complaint then this would be the lower heights to our N would prevent a very cold pool from moving S but then again it could be cold enough for a major snow event. However with the lack of decent heights to our N it wouldn't be very long before the N,ly flow was toppled.

Just read Joe B latest forecast and he suggests short lived cold spells before winter really kicks in for mid-late winter.

Maybe just for once the mild spells will be short lived and its the colder spells that will be dominant this winter!

[Snowmad79]

My My looks like all this evenings model runs are swaying to that of this mornings GFS. even the ECM is now showing that similar HP retrogressing north from the middle of the atlantic although not quite establishing iteself just to our north as shown of the GFS. Never the less I agree with what WIB said this morning that models are playing catch up atm.

To behonest I aslo think theres still some lag in the Lastest UKMO faxes Re the current situation with regards to LP cells on or around us. Ive been watching the satillite imagary for a couple of hours and two area of cyclonic vorticity ( if thats what you call it lol) are already evident the positioning is different to the 00 fax and does appear to be moving S and E. Not sure if this has any relevance as to models, just thought id mention it.

FAX

[cooling climate]

Certainly seems as if another reloading cold pattern on the way from the models tonight which they

will hopefully reinforce over the coming days.

You are quite right though Nick we are being spoilt rotten at the moment and we would have normally

have given anything for the synoptics on view this evening.

Here in Hertfordshire for snow lying and cold in December I think you would have to go back to 1981

to beat it.

Being a tad greedy here but if that low that came down from Svalbard on Saturday tracked more s/e

then I think a white Christmas would have been odds on for all in the UK + the cold would have been

even more potent.

[ukmoose]

UKMO 12 z fax's

http://www.wetterzentrale.de/pics/brack0.gif

http://www.wetterzentrale.de/pics/brack0a.gif

http://www.wetterzentrale.de/pics/brack1.gif

http://www.wetterzentrale.de/pics/brack1a.gif

Actually might get some decent snowfall here at last from that, more in line GFS 12z

xmas day, increased blocking

http://www.wetterzentrale.de/pics/brack2.gif

00z fax for xmas day.

http://www.wetterzentrale.de/pics/brack2a.gif

Mark

Teesdale,Co Durham

I'm no expert, but I don't like the look of the fax chart for Christmas Day. HP looming large over Spain and a LP system waiting in the wings. Someone please tell me I"ve not read the chart correctly because that doesn't look pretty to me.

[Frosty.]

It is interesting to note that after forecasting a push towards milder weather now, tv forecasters have become more tenentative again and are forecasting snow "in the north" as early as Boxing Day.

Some warm-up!

I noticed that too, quite incredibly there is a good chance of the rain which moves in on boxing day turning to snow in scotland before the colder air and snow risk begins to push south towards england by early next week. The ecm 12z is superb, as others have commented, and it's only 4 days before the cold could begin to intensify in the far north before the NE'ly pushes arctic air south to all areas as the ecm shows with scope for more heavy snow and disruption.

[cheeky_monkey]

mild spells might last as long as cold spells from recent years, infact even shorter lookign at this upcoming blip, infact not a blip for here.

it can onyl get better for my part of the world astonishing because we have had snow on the gorund since last thursday and then comes ecm and throws somethign which will put current snow to shame lol.

cant see any major snow event south of birmingham on the ECM...lookS better to me for a country wide snowfall on the GFS

[nick sussex]

Certainly an interesting trend from the models just after xmas. If I had one complaint then this would be the lower heights to our N would prevent a very cold pool from moving S but then again it could be cold enough for a major snow event. However with the lack of decent heights to our N it wouldn't be very long before the N,ly flow was toppled.

Just read Joe B latest forecast and he suggests short lived cold spells before winter really kicks in for mid-late winter.

Maybe just for once the mild spells will be short lived and its the colder spells that will be dominant this winter!

I wouldn't worry about the lower heights to the nw on the ecm for the timebeing, we still have a little hurdle to overcome before this with seeing what sort of phasing happens with the UK low and the one coming in from the sw. IMO the safest route back to cold is the gfs view. In terms of lower heights to the north, as long as the PV remains unstable we could still get a high near Iceland and as long as some energy keeps the southern arm of the jet propping up any block near the uk then that would be okay.

[Optimus Prime]

The outlook remains very much against the grain in comparison to what we've seen since 1997. Greenland blocking and Low Pressure tracking towards the south.

This is about as good as it gets for looking at sustained cold. A bit like 78/79.

[Michael Fishermans Friend]

Yeah have to agree very strange looking synoptics have been occuring over the last week and looks like into the foreseeable future, at the present LP's all over the place apart from well to our north but looks like a trend developing now for the jet to be squeezed just to our south and sustained cold to our north and in the middle - who knows! hopefully we'll all be on the right side.

[casparjack]

Only just had a look at the ECM 12z, seems to be a reversal of the ideas that were developing yesterday, this cold air seems to be rather more stubborn, rather like the old days...

Off to have a look at the other models now, with renewed enthusiasm!

[TEITS]

Well the ECM ensembles are interesting.

http://www.knmi.nl/exp/pluim/vijftiendaagse/Data/15DAAGSE_06260_NWT.png

The mean remains at 0C apart from a very shortlived milder blip which isn't worth really mentioning.

[karyo]

Well the ECM ensembles are interesting.

http://www.knmi.nl/exp/pluim/vijftiendaagse/Data/15DAAGSE_06260_NWT.png

The mean remains at 0C apart from a very shortlived milder blip which isn't worth really mentioning.

That's a pleasing set of ensembles! The mild blip is probably associated with the time we have the low pressure over the UK so there should be a brief southwesterly over the low countries before it gets cold again.

Karyo

[Osbourne One-Nil]

In the short term the trend is towards milder conditions and I'm far from convinced that a return to cold is a given post Xmas.

Yep, I'm starting to pick up on that.

[TEITS]

I tell you what Worzel for someone who says they enjoy cold weather you do a damn good job at looking at the milder option. This reminds me of another poster from the SW. I wonder who that could be.

Having said this you do have a point but at the moment the trend from the main models is excellent.

Looking at the 18Z and to be honest the only place that becomes milder is the S. Also when you have a chart like below then the cold will always be nearby. Still I fancy a brief warm up after 9 days of sub zero temps!

Edited December 22, 2009 by THE EYE IN THE SKY

[Bristawl Si]

I tell you what Worzel for someone who says they enjoy cold weather you do a damn good job at looking at the milder option. This reminds me of another poster from the SW. I wonder who that could be.

Having said this you do have a point but at the moment the trend from the main models is excellent.

Completely off topic i know, but talking of one of the south west posters - what's happened to Jemtom this winter?- last year he was a very frequent poster. Anyone know?

[Nick L]

Completely off topic i know, but talking of one of the south west posters - what's happened to Jemtom this winter?- last year he was a very frequent poster. Anyone know?

I think Jemtom maybe the member who TEITS was referring to. I think he said he was taking a break after getting quite a lot of stick last winter for being negative.