General Model Output Discussion

[wysiwyg]

The 12Z is back to taking an more organised band of light precip down the country Saturday night as it makes more of the small low pressure trough/front.

It still looks likely to be a convective feature to me. There is no discernable WAA from anywhere other than the warm sea below that feature. Again I suspect that the precip band is modelled on a "likely to see showers" basis and will not necessarily be an organised frontal band of snow moving south. Also I think that the scottish highlands will take any sting out of the precip and the best chance for anywhere south of the Highlands is for local coastal convection as the feature moves south and temporarily modifies the flow direction. Having said all that - looking at the current satellite pics it does look quite organised already over Norway so who knows? - lamposts at the ready!

[Thundery wintry showers]

An obvious precipitation upgrade on the 12Z. I also believe that precipitation is modelled to be convective rather than frontal, but with the low being progged further west with each run, it creates a more prominent westerly flow for western areas early on the 2nd, and then a more prominent cold easterly flow for eastern areas late on the 2nd and through to the 4th. The result- an easterly loaded with convection instead of a mainly dry one.

The snow upgrades mainly concern eastern areas because in the west, the westerlies draw in slightly more modified air making conditions more marginal out towards western coasts especially for Wales and south-west England.

[Iceberg]

It still looks likely to be a convective feature to me. There is no discernable WAA from anywhere other than the warm sea below that feature. Again I suspect that the precip band is modelled on a "likely to see showers" basis and will not necessarily be an organised frontal band of snow moving south. Also I think that the scottish highlands will take any sting out of the precip and the best chance for anywhere south of the Highlands is for local coastal convection as the feature moves south and temporarily modifies the flow direction. Having said all that - looking at the current satellite pics it does look quite organised already over Norway so who knows? - lamposts at the ready!

GFS looks to pep it up a bit as it moves close to the M4 corridor, it will be interesting to see what the NAE makes of it and the NMM.

This is quite a different set up, it pushes the potential channel low all the way down to portugal by 96hrs and enhances the LP coming out of norway.

Quite strange really.

More showers in the first part of the week SE of a line from the wash to the IOW, the normal gaps prone to a NWerly and the North of Scotland. Very little wind, very slack and slow moving.

[❄️❄️❄️❄️❄️❄️❄️❄️❄️]

A nice amount of sub -10C getting across the UK on Monday

With appropriate max and min temps:

Edited December 31, 2009 by RAIN RAIN RAIN

[nick sussex]

GFS looks to pep it up a bit as it moves close to the M4 corridor, it will be interesting to see what the NAE makes of it and the NMM.

This is quite a different set up, it pushes the potential channel low all the way down to portugal by 96hrs and enhances the LP coming out of norway.

Quite strange really.

More showers in the first part of the week SE of a line from the wash to the IOW, the normal gaps prone to a NWerly and the North of Scotland. Very little wind, very slack and slow moving.

Yes at this rate i could find myself on the northern flank of the low! it certainly looks like a major snow event for central France and overall the gfs looks like delivering a wonderful run for the UK.

[Neilsouth]

A very bitter monday across the uk

http://91.121.94.83/modeles/gfs/run/gfs-1-102.png?12

Tuesday -12 moves across the south east!

http://91.121.94.83/modeles/gfs/run/gfs-1-120.png?12

[winter watcher]

What's all the talk and utter nonsense being made from a few posters about 'Bad run no snow' OR 'To Dry' Fair enough if your a very new member than you should be forgiven but i have seen more experienced posters saying these sort off things and it gets on me nerves to be frank if you use your loaf's and think right what are we looking at here 'Ok Two to three weeks possibly longer off very cold temps' Also 'As John said earlier 95% off the country are likely to see some snow before its over with don't know how much or what day or time but it will come' And something young folk has not seen in all there life i,e Severe Cold Weather and not just a two day event. Come on all its new years eve a time to be happy and a time to celebrate and not time to be getting angry over model runs which has virtually no chance off predicting and pin pointing snow 24-48 hours out let alone 2-3 weeks. Happy new year to all and truly hope you all have a safe and stress free beginning to 2010

[Iceberg]

Again Tuesday night another more organised front/convective feature/trough moves down from scotland, thru north england, central england and the east, thru wed and into wed evening it finally makes it to central southern england.

These details will certainly change run by run, but the picture of more precipitation in the form of showers and light organised troughs is definately emerging on this run.

Yep Nick, any chance for the SW to get snow quickly gots titsup, with somebody else to benefit from

Edited December 31, 2009 by Iceberg

[Iceni]

Thanks WIB

I'm shocked if they have cancelled the celebratons, what more perfect a scene can you have than snow falling and welcoming the New Year in, let me guess it was done on safety grounds in case someone slips on an icy pavement and then sues the council! what a shame if they have cancelled them i mean what a shock snow falling in winter! didn't they think of this beforehand!

Snow does blow around — perhaps it's because they'll be wearing kilts?

[nick sussex]

OMG the UKMO is sensational upto 120hrs!

[Optimus Prime]

OMG the UKMO is sensational upto 120hrs!

A better orientation on the Greenland high and as a result, over the 12Z a better, colder and snowier NE'rly.

[Richie V]

OMG the UKMO is sensational upto 120hrs!

Steady fella sit down and breathe deeply into your paper bag.

Whoaaa, I see what you mean, give that bag here

-25c anyone

Edited December 31, 2009 by Chassisbot

[If Wishes made Weather]

This may be slightly off topic, but looking at the radar ATM, the showers coming in off the North Sea are clearly organised in lines or bands. Movement of the showers is along the band, as well as the bands moving slowly SE in themselves. What causes this, clearly its not topographic over water?

[Stu_London]

CET - Jan01 - Jan07 as per GFS 12z - -1.6C

[kold weather]

Well the 12z is similar with timings to the 06z but a good deal further west and thus we hold onto a decent easterly flow for much longer it seems on this run...

Gotta say its a nice run thus far for cold weather!

[weather eater]

I'll have a look at the UKMO in a bit, the GFS 12z is looking very interesting, its much slower in sinking the high and keeps it further west keeping us in a very chilly airflow.

[PB22]

A frigid run from the 12z UKMO...there's barely any change in the evolution between T+120 and T+144:

T+120:

T+144:

Fascinating, and very cold, times ahead.

[Neilsouth]

Great run ! , very cold probably the coldest in a good few years

I wonder if i'll see Lake Fordwich freeze up again in kent

- Paul B , that might be why the met mentioned heavy snow risk on monday

Edited December 31, 2009 by neilsouth

[Cloud 10]

OMG the UKMO is sensational upto 120hrs!

The +144 isn't bad either...

[Paul]

Anyone ever seen the signs in car parks - "So far this week xx cars have been clamped for not paying and displaying".

Well here's the netweather version:

So far in the last 48 hours 4 people have been stopped from posting for continuously posting off topic in the model threads (despite direct and indirect requests not to)

Based on this morning's posts we could easily double that as some posters aren't just posting the odd off topic or wandering post (which is fair enough), but they're posting off topic time after time in here. There's no valid reason to do it, there are plenty of other threads available (including a model chat thread for the shorter, more light hearted model related comments), so it's just laziness and a lack of respect for the other members of the forum, and with that in mind we have no qualms whatsoever in stopping the worst offenders from posting...

No apologies for reposting this...

[SMU]

Chart of the day for ENGLAND-

http://91.121.94.83/modeles/gfs/run/gfsnh-0-162.png?12

Sub -10c across the country- perfect Easterly flow 265 degrees- heavy snow moving snow showers-

I am still very happy with the GFS evolution- because of the negative zonal wind anomlies then the toppler is SOOOO slow the Easterles get re embedded-

UKMO 144 on a very similar wavelength-

GME-

http://91.121.94.83/modeles/gme/run/gme-0-132.png

All models now pos tilting the block on the top end forcing the flat easterly on the bottom side......

FAB FAB day so far

I bet the 12z GFS ensemble mean is between -8c & -10c @ 180

YESSSSSSS !!!

http://91.121.94.83/modeles/gfs/run/gfsnh-0-180.png?12

Steve

Edited December 31, 2009 by Steve Murr

[nick sussex]

Steady fella sit down and breathe deeply into your paper bag.

Whoaaa, I see what you mean, give that bag here

The ukmo at 144hrs is even better with some extremely cold air having been pulled wsw, imagine all that Lake Effect Snow from the North Sea, unbelievable, i need to go and lie down! Just wonderful charts for the uk and even here i get some snow as the low clears away! altogether a great start to the evenings model output!

[sandstorm2]

Truly sensational charts from the GFS and the UKMO, in the not to far FI land about 168 there looks to be a beast from the east trying to muscle its way in,. Don,t think weve seen charts like these since the advent of the internet.

SS2

[Iceberg]

Yep a stunning METO, It keeps the band of light precip as well over the weekend, also the precip begining of next week and finishes with lots of precip for the south by mid week.

GFS is looking like a stunner longer time range. with the PV dropping out of Scandy, forcing the high back NW and also the added benefit of some bands moving into the SW providing snow there.

However well into FI now and tbh nothing beyond 144Z however good is really to be believed.

[Optimus Prime]

Chart of the day for ENGLAND-

http://91.121.94.83/modeles/gfs/run/gfsnh-0-162.png?12

Sub -10c across the country- perfect Easterly flow 265 degrees- heavy snow moving snow showers-

My god, that's one of the best wintry chart I've ever seen go live (aside from the historic ones)