Model Output Discussion - 12th December Onward

[phil nw.]

Thanks to you and bluearmy for replying, so it is unusual to see on 850mb but its not quite what it looks like on there, still trying to fully understand your answer from earlier, in weather terms. Its great that i can still come on here and learn something new with the models, and i thought i had a good understanding of them.

Cheers both

Just a quick one from as i am off soon.

here on 18z GFS

http://www.wetterzentrale.de/pics/Rnamavn842.png

A patch of warm uppers W.Canada.

A High off the Pacific coast -warm winds from the ocean and warmer still after decending over the Rockies--that may be why they are higher 850`s there.

The actual ground temps. are well below freezing

http://www.wetterzentrale.de/pics/Rnamavn849.png

--typical continental climate and very low dewpoints.Inversion --warm air aloft but cold air trapped at the surface.

[Frosty.]

The change to milder weather next week will take until wednesday to really take control but it may only last 2 or 3 days with temps then returning to near average or slightly below, at least for northern areas. I don't think we are going to have a prolonged mild spell as such, more likely there will be brief colder shots between but next week looks mild between wed and xmas eve at least, the Ecm 12z at the end of it's run hints at cold zoneality returning with snow across the north by boxing day.

[Thundery wintry showers]

Just a zonal express really, a standard flat zonal pattern with temperatures above average in the south and close to average in the north. It's worth noting that this run again has a polar maritime incursion on Christmas Day which would bring wintry showers in the north (snow on high ground, a wintry mix at low levels) if that run verified.

[Cloud 10]

The cfs is the new pub run. :lol:

[ZONE 51]

http://www.personal.psu.edu/adb241/eWallTutorial/models/gfs.htm

http://www.personal.psu.edu/adb241/eWallTutorial/models.htm

Good site, all about the models and what everything means, how to use the models...

(please move post if needed)

[ZONE 51]

Has anyone seen this model before,

http://www.westwind.ch/?page=theu

Edited December 17, 2011 by ElectricSnowStorm

[snow drift]

Just a zonal express really, a standard flat zonal pattern with temperatures above average in the south and close to average in the north. It's worth noting that this run again has a polar maritime incursion on Christmas Day which would bring wintry showers in the north (snow on high ground, a wintry mix at low levels) if that run verified.

The only real interest would be if the fllow moved a bit further South which would in turn bring the pm air over more of the country. Hopefully so, to give a more seasonal feel to the holiday period.

[Cecil Hogmanay Melchett]

One has to say the models this morning are pretty much as guff as they could be!!

Looking very much like the vasy majority are going to be snowless for the last 2 weeks of December with a strong NAO and as flat a pattern as you could wish to see.

On that note peeps im having a good look outside at the beautiful white landscape because it might well be next year before i see anything similar.

[weathe20]

More normal UK winter fare (im bored of posting this, will probably stop till next winter) Milder next week, then maybe PM and milder incursions throughout. Some wintry stuff for the North with the PM incursions but appart from that just a........

bor-fest.

Hope Santa brings something for all you coldies out there......seems you all have been naughty boys and girls this year.

[mountain shadow]

Classic zonal weather right out to the end of FI. Ridge-trough-ridge-trough......etc.

Should be plenty of rain around and with the close proximity of the jet to the uk and a large temperature gradient another big storm cannot be ruled out.

[Frosty.]

The Gfs 00z operational run shows a 36-48 hour mild spell spanning midweek but with rPm air chasing the mild air away by thursday night and then we are back into a cooler zonal pattern and a block of cold air rushing east from a canadian formed depression just in time for christmas across northern britain with a risk of snow showers in n.ireland and scotland on the 25th, then less cold by boxing day but then possibly cold again a few days later. FI is cool zonal express with much smaller mild interludes but even by Jan 1st, the gfs is still showing high pressure itching to move north from southern europe and send the jet further north again so there is still no sign of a major pattern change for a while yet but at least it's not going to be mild for the next 2½ weeks either!!

Edited December 17, 2011 by Polar_ Low

[johnholmes]

the 500mb anomaly charts, over the past couple of days have kept the +ve area around the Azores but tended to drop heights slightly over the UK area. Its still shown as a pretty strong W'ly type flow over most of the Atlantic into the UK. So maybe less emphasis on milder and more on the coldish zonality. Always the risk with the contrasting temperatures north to south in the western Atlantic for another deep low to occur. I suspect the 500mb flow will move between the two types suggested in the 3rd sentence over the next 2-3 weeks. Little sign of any major wave length change from further out teleconnections at the moment.

Edited December 17, 2011 by johnholmes

[phil nw.]

A cold weekend then with pressure gradually rising from the south into next week turning things gradually milder.

The flow turning more into the west by midweek.

http://hw.nwstatic.c.../h850t850eu.png

http://hw.nwstatic.c...ecmt850.120.png

http://hw.nwstatic.c.../00/met.120.png

A standard zonal pattern then going forward.

It looks like temperatures will gradually rise and by midweek it will become quite mild for a short while.

Some brief colder incursions look likely towards the Xmas weekend,especially further north as the polar front wavers North and South across the UK .

Edited December 17, 2011 by phil n.warks.

[ANYWEATHER]

More normal UK winter fare (im bored of posting this, will probably stop till next winter) Milder next week, then maybe PM and milder incursions throughout. Some wintry stuff for the North with the PM incursions but appart from that just a........

bor-fest.

Hope Santa brings something for all you coldies out there......seems you all have been naughty boys and girls this year.

I have to say that running through the gfs I Would have to disagree with you there! A few days ago the model runs did look a bit tedious, but now there seems to be plenty of scope for some action packed weather, over the xmas period and into the New Year Period. Certainly cant rule out another Stormy spell of weather and some spells of cold weather in the near future, similar to what we have had so far this month...... :smilz38:

[shedhead]

A cold weekend then with pressure gradually rising from the south into next week turning things gradually milder.

The flow turning more into the west by midweek.

http://hw.nwstatic.c.../h850t850eu.png

http://hw.nwstatic.c...ecmt850.120.png

http://hw.nwstatic.c.../00/met.120.png

A standard zonal pattern then going forward.

It looks like temperatures will gradually rise and by midweek it will become quite mild for a short while.

Some brief colder incursions look likely towards the Xmas weekend,especially further north as the polar front wavers North and South across the UK .

Pretty much sums it up for me Phil, but looking beyond Xmas I'm still struggling to see how things are going to change much, at least through until New Year. Whether we can then get heights to rise to our north

through early Jan remains the big question, but frankly I wouldn't be surpised to see this zonal pattern lasting for another week or two once it gets re-established; hopefully if it does though it will again be of the

colder variety.

[bluearmy]

i am struggling to see how the build in pressure over the siberian arctic with the introduction of an cold acrtic high will fail to change things this side of the NH. already seeing the warm russian high being pushed south and east on the fi output. i would have though that we must see a change in tone to our zonality as the tilt of the flow changes or even maybe the azores high ridging into us. in years gone by, there was the old adage that lack of monitoring stations in the arctic meant that this region was badly modelled. was this a myth ? is it still relevant ?

[phil nw.]

Pretty much sums it up for me Phil, but looking beyond Xmas I'm still struggling to see how things are going to change much, at least through until New Year. Whether we can then get heights to rise to our north

through early Jan remains the big question, but frankly I wouldn't be surpised to see this zonal pattern lasting for another week or two once it gets re-established; hopefully if it does though it will again be of the

colder variety.

Well as John H as posted above there is nothing to suggest any radical changes in the mean 500hPa pattern in the next 10 days or so.

I think any Wintry stuff will come from those brief Pm incursions as the PFJ moves south over the UK .The flow is modelled to a very flat W-E and with the High very close to the south at times,there`s not a lot of room for a cold shot in the south.

These say it all really,

http://www.wetterzentrale.de/pics/Rtavn1921.png

http://www.wetterzentrale.de/pics/Recm1921.gif

Hopefully at some point we can see some buckling of the jet to at least bring some minor changes-even if we do get stuck with zonal for a while.

[Frosty.]

the 500mb anomaly charts, over the past couple of days have kept the +ve area around the Azores but tended to drop heights slightly over the UK area. Its still shown as a pretty strong W'ly type flow over most of the Atlantic into the UK. So maybe less emphasis on milder and more on the coldish zonality. Always the risk with the contrasting temperatures north to south in the western Atlantic for another deep low to occur. I suspect the 500mb flow will move between the two types suggested in the 3rd sentence over the next 2-3 weeks. Little sign of any major wave length change from further out teleconnections at the moment.

That is how I see it, average december atlantic dominated pattern with fleeting cold incursions and mainly cool zonal rPm type flow, especially further north apart from the much milder few days midweek, maybe a white christmas for hilly areas in scotland only.

[wolvesfan]

Morning all,

Models continuing to show us cold fans what we don't want to see(average/mild synoptics).We shouldn't be surprised though stratosphere still anomolously cold,polar vortex still strong,+NAO,+AO.

The odd NW incursion probably the best we can expect until we see some significant change(if we ever do).

[WhiteFox]

i am struggling to see how the build in pressure over the siberian arctic with the introduction of an cold acrtic high will fail to change things this side of the NH. already seeing the warm russian high being pushed south and east on the fi output. i would have though that we must see a change in tone to our zonality as the tilt of the flow changes or even maybe the azores high ridging into us. in years gone by, there was the old adage that lack of monitoring stations in the arctic meant that this region was badly modelled. was this a myth ? is it still relevant ?

Until we get a more favourable upstream pattern, it's irrelevant what the siberian high gets up to. Every winter that has long periods of zonality sees the so seismic high pushing further west, but in most cases the farthest it gets is central Europe. With just the right setup it can push farther across as in 1987, but you have to rely on so many things happening at exactly the right moment, that is why the extreme outbreaks such as Jan 1987 are as rare as hen's teeth.

Until the jetsream stops flying off the east coast of north America, the best we can hope for is some amplification and colder shots/topplers.

[BLAST FROM THE PAST]

Yep we're looking at a less cold/milder spell again, as expected isn't it? Reading some posts its as if there's a told you so to coldies? Anyone been predicting a freeze?

What is to look out for is the good possibilty of further gales and around Boxing day could be stormy for 'most'

Really cold here again today...yep cold.

BFTP

[bluearmy]

Until we get a more favourable upstream pattern, it's irrelevant what the siberian high gets up to. Every winter that has long periods of zonality sees the so seismic high pushing further west, but in most cases the farthest it gets is central Europe. With just the right setup it can push farther across as in 1987, but you have to rely on so many things happening at exactly the right moment, that is why the extreme outbreaks such as Jan 1987 are as rare as hen's teeth.

Until the jetsream stops flying off the east coast of north America, the best we can hope for is some amplification and colder shots/topplers.

except i'm not thinking that this "siberain" arctic high will sink into russia. the arctic high that is currently modelled is meandering around closer to the pole than the siberian mainland. my point is that should such a feature verify, could it not affect the tone of the zonal flow this side of the NH ? who knows, it might affect the placement of the ne canadian p/v which has been and continues to feed the zonality. hence we could see a change to the axis of the zonal flow and maybe even a change to the mean conditions in nw europe as a consequence.

[Timmytour]

I've seen depresing models in previous years where the pattern to our west sweep right through the UK all the way through to Siberia. It's one thing I've not really seen this time with everything stalling in Europe despite the apparent absence of a dominant high pressure system.

I'm minded to think that this presents prospects of an increasing eastern influence on our weather in due course.....I'm looking for a date of around 15th January when this easterly influence exerts itself after the Atlantic influence wanes from about the 6th

[SP1986]

I've seen depresing models in previous years where the pattern to our west sweep right through the UK all the way through to Siberia. It's one thing I've not really seen this time with everything stalling in Europe despite the apparent absence of a dominant high pressure system.

I'm minded to think that this presents prospects of an increasing eastern influence on our weather in due course.....I'm looking for a date of around 15th January when this easterly influence exerts itself after the Atlantic influence wanes from about the 6th

I've seen depresing models in previous years where the pattern to our west sweep right through the UK all the way through to Siberia. It's one thing I've not really seen this time with everything stalling in Europe despite the apparent absence of a dominant high pressure system.

I'm minded to think that this presents prospects of an increasing eastern influence on our weather in due course.....I'm looking for a date of around 15th January when this easterly influence exerts itself after the Atlantic influence wanes from about the 6th

I think although it looks slack the siberian high is still there exerting an influence, but even in a zonal winter it's a tough one to remove, as the Siberian high is a semi-permanent high by nature, so it's not surprising it's having a lot of blocking power to those lows coming in, on the model predictions.

[January Snowstorm]

Yep we're looking at a less cold/milder spell again, as expected isn't it? Reading some posts its as if there's a told you so to coldies? Anyone been predicting a freeze?

BFTP

Yes you and Roger lol