Winter Model Discussion - The Hunt For Cold -18z 17/12/12

[Zakos]

Looking much better so far on the 18z

1058mb high over Greenland!

[Panayiotis]

Shortwave heaven in the 18z for the 26th! http://cdn.nwstatic.co.uk/gfsimages/gfs.20121219/18/156/h500slp.png

[Geordiesnow]

High over greenland 10mb stronger but russian high further west (144h)

A polar Northerly is unlikely to occur as there is no WAA going into Greenland, I don't think I ever seen a Northerly occur from high pressure dropping from the Canadian side of the Arctic into Greenland?

What the output is showing that Xmas day could well be cooler than first thought and if the set up angles itself correctly, there may be a white Xmas for some in NW Scotland in particular.

Still a way to go though, plenty of weather coming up in terms of rainfall, shame the cold potential even in parts of Scotland is nearly all but gone now.

[chris55]

Not a bad Boxing day chart,

[nick sussex]

The GFS splits the energy upstream at 168hrs, Amen to that!

This needs to happen!

If you get this you might get some retrogression of the Azores high.

Edited December 19, 2012 by nick sussex

[TEITS]

Some silly posts this evening, a displaced Bartlett HP!

Anyway the 18Z just confirms my post earlier and that is from Boxing day onwards the chance of cold NW/N,lys remains a possibility. This is especially true for Scotland, N England.

I do wish when members comment on the model output they take the whole of the UK into account. What might be disappointing for my location may not be the case for others.

[Ruzzi]

That displaced bartlett over greenland looking slightly stronger on this run.

[karlos1983]

Sorry, can somebody give me a quick explanation of WAA?

Thanks

Karl

[Duane S.]

Yes, me back at the end of winter last year where I did a brief synopsis of what I expected spring- summer to bring, based mostly on CFS/ECMWF long range and gut instinct. CFS was plugging a wet summer months beforehand.

Then, back in autumn (October time) I was quite blase about how I expected Nov and Dec to be Atlantic driven.....against what many people expected.

It's not that no-one expected it, it's that no-one wanted to entertain the idea.

CC, you are a sensitive soul, do we need to continually reminded about how you told us abc was going to happen in the year xyz and that nobody evers listens to your wisdom???

No change on the model front today, upper troughing edged eastwards overall but still very much in control of our weather for at least the next 7 days by the looks of things

[Zakos]

much better ridging in the atlantic on this run than on the 12z.

will it keep the atlantic at bay?

I think so

Edited December 19, 2012 by Zakos

[-uksnow-]

A definite shift eastwards on the 18z, looks better already... and whats this?!!?!?

[Panayiotis]

Love the 18z so far, could get very interesting after Christmas! To show the potential, yes it shouldnt be taken much into account as its Fi IMO but always nice to see!a

[Harsh Climate]

That displaced bartlett over greenland looking slightly stronger on this run.

Edited December 19, 2012 by Harsh Climate

[snowmadchrisuk]

smashing channel low , Snow event on the 27th from the 18z ..... look at all the SW;s diving SE and the Jet is heading back south .... Best run I've seen for a few days .

[Geordiesnow]

Some silly posts this evening, a displaced Bartlett HP!

Yeah that a new one for me, its not unusual for pressure to be high across Europe to start off with - its normally the norm really. either way, its very unlikely we will be influnce by a Bartlett high anytime soon.

[ICETAB]

The GFS excites me from an IMBY POV. Not often the west sees potential like this...

Edited December 19, 2012 by ICETAB

[Panayiotis]

Sorry, can somebody give me a quick explanation of WAA?

Thanks

Karl

Stands for warm air advection, here you go nice website for definitions NOAA's National Weather Service - Glossary (click on W) Edited December 19, 2012 by Panayiotis

[SnowBallz]

Sorry, can somebody give me a quick explanation of WAA?

Thanks

Karl

Warm Air Advection.

Think of it like a massive hair dryer being turned towards the Artic.

[karlos1983]

this just doesn't look right!! has somebody been on the sauce

[snowmadchrisuk]

-10's into Cornwall still in high resolution ..... oh please don't be an outlier

[nick sussex]

You`re not the only one Ed-i looked it up too.

In that context i would think more extensive polar heights-more central?Hence my little ramp that the Uk may be impacted later.

Maybe they have a possible SSW in mind?

Phil the mystery behind the canonical negative AO maybe here, I've just skimmed it but its excellent for many other things, one of the best articles I've seen on the MJO etc, I'm not sure if GP has this but its really interesting.

http://iprc.soest.ha...ed_withFigs.pdf

Phil you need to look at page 42, cluster 4.

Edited December 19, 2012 by nick sussex

[A.J]

Sorry, can somebody give me a quick explanation of WAA?

Thanks

Karl

Warm Air Advection.

Think of it like a massive hair dryer being turned towards the Artic.

bang on.....

Not a lot of people know this, but it's also the wailing sound that 'coldies' make when the model output shows blow torch south westerlies over the entire country for days on end!

[Spurry]

Why are people raving over the 18z tonight? , when normally it's just dismissed as 'The Pub Run'..if this was twitter it would have the hashtag #clutchingatstraws..i hope it comes to fruition but it's not normally seen as a reliable run.

[Bristawl Si]

this just doesn't look right!! has somebody been on the sauce

GFS 18z has been on the sauce for about 10 days now! It's been churning out completely different runs for over a week!

[Great Plum]

http://www.wetterzentrale.de/pics/Rtavn2401.png

It appears in FI that the displaced Bartlett is too far west of Greenland...