Winter Model Discussion 06Z 10/01/13>

[Staffordshire]

Only problem with this gfs run is that it has been very iratic of late and next weeks snowfest could be gone of the model by the next run

[peterf]

I have to agree about the cold temperatures, if it came off, they would most likely be similar to 2010, but I suspect this time more central west orientated... excellent for cold lovers, but an absolute disaster for agriculture and horticulture.

i work in both industries,it will be troublesome but not a disaster.nature always puts things right again.

[snowking]

Right so ECM32 control

General theme is pressure high to the north, and low to the south of the UK, with some slight variation on that theme as we enter February (more of a mix of PM and true Polar air masses) but I would expect such an occurrence at this stage.

Over to the ensembles in the morning then!

SK

[mulzy]

ECM Ensembles remain cold (though some moderation from the cold is indicated in FI). Operational again on the milder side for days 4/5 (this is when the shortwave drops south).

[pyrotech]

Im sure some members will want an overall outlook of what the models are showing for this weekend into next week so here goes. Do not take as gospel though because especially from Monday onwards its still uncertain.

Saturday.

Rain in the S with snow on the N flank especially SE Wales/SW Midlands area. Those areas who are seeing rain could see this turn to snow before it clears S.

http://expert-images...011218_1018.gif

Sunday.

Snow showers in E areas with areas such as Lincs/Humber look most likely to see heavier snowfalls although this could extend into Norfolk. Will add im not ruling out snow in other E areas.

http://www.meteociel...ax72s.gif?10-12

Monday.

Rain moving E turning to snow across central areas of the UK and most probably weakening as it reaches the far E of the UK. The areas that could miss out on snow is possibly Wales, Ireland, SW England, W Scotland.

http://www.meteociel...x120s.gif?10-12

Into the rest of the week is tricky to predict. I would suggest remaining cold with the colder temps spreading back W. At the moment the SE could be the coldest part of the UK and snowfalls could occur spreading from the W across the UK.

Hope this helps.

TEITS i agree thats what the charts show now, but we should make sure newcomers are aware that all thats important at that timescale is likelyhood of cold and likelihood of percipitation, we know that even saturdays event will change for Snow/Sleet/Rain and extent North or South.Further into the week the will it snow IMBY will change even more, personally i expect upgrades as the cold air digs in and it being denser than the Modified Atlantic air, however to be accurate it could alter either way. Very positive run from GFS and some cross model agreement makes next week much more likely.

[Panayiotis]

When the -8C minima comes up for the extended forecast you something is coming! Ive always had a look at the extended forecast and Ive noticed that when cold weather is coming the minima drops quite a bit into negative values. Eg < -3C

Edited January 10, 2013 by Panayiotis

[SandraD77]

Your looking at the wrong models then Sandra.

Both tonights GFS and the ECM would bring plenty of snow it Ireland

Uppers of -4's -6 only... not looking at models output beyond beyond t120 (on GFS 18z) at moment as FI to difficult to call considering the recent uncertainity! So not good for Ireland just yet!

[rory o gorman]

ecm does good for ireland . the north and east especially undercutting low . GFS is not quite there yet .

[SP1986]

i work in both industries,it will be troublesome but not a disaster.nature always puts things right again.

A local garden centre lost £10,000 of stock in the 2010 cold spell, a good proportion of that was very expensive Wollemi Pines. That was a disaster for the company.

Looking at the models, if we can believe the GFS output, and seeing the potential for severe frosts if it does, then a repeat may occur.

[Stoxs]

I have to agree about the cold temperatures, if it came off, they would most likely be similar to 2010, but I suspect this time more central west orientated... excellent for cold lovers, but an absolute disaster for agriculture and horticulture.

why?

Not really going to effect any agricultural business this tiem of year unless the gorund stays frozen for weeks on end. Winter crops that are planted will be fine.

Most in agriculture will enjoy being able to move around without mud upto there

knees!

Any way very interesting model runs today, picture changing every time, I think the 18z GFS as swung to far slightly

but i would be happy to eat yellow snow if its wrong.

And today in the model thread i saw my first Polar Low mentioned! PMSL,

not bad as it is usually mentioned first in November when the first frost arrives.

I think we are long way from such events as Polar Lows, but a welcome relief if it verifies after the dredded december 2012 !!!

Still think next week is up for grabs and we will see small changes but in this situaton can make a big difference.

[Paul T]

If people have read some of the things that I have intimated over the years & what ian has confirmed in his posts over the weeks-

* The GFS has poor handling of high pressure systems to the NE- it always has-

* The GFS has a strong atlantic bias- particular on the 06z & 18z suite- especially the ensembles- ie to much energy

* Exeter, whilst viewing the 06z dont take any stock really, all they do however is use it to determine confidence- I have NEVER seen the fax chart modified to the GFS away from UKMO/ECM

* The ECM ensembles & mean are a LOT keener on a the shortwave dropping south than the GFS-

* The fact that the METo have updated next week to ignore the entire GFS shows there is zero confidence-

* THe ARPEGE info MUST be strong-

here is the 12z predictions

UKMO- no change

ECM- westward correction to the UKMO with respect to mondays low-

GFS- a big SW correction & 50% of the ensembles move to the EURO solution.....

S

Before I start any posting and analysis tonight, can I just highlight the post from Steve earlier. After seeing a poor GFS I read this on my brief lunch break with confidence...and it bloody delivered. Very solid forecasting Steve.

[Southender]

Fantastic day and monumental tail between the legs moment for the GFS. We must however see this pattern firmed up on overnight runs. That is crucial. How many times have we seen close to cross model agreement, for one suddenly to jump off. Just as the GFS has done over the last 2 days. The 18z as we know is not exactly a trustworthy run either!

Fingers crossed we all wake up with the big 3 singing the same tune. I'm sure we have all had enough of the drama for a few days. And we want to firm up on how cold, how snowy and for how long. Rather than worrying about getting the cold in for once!

A great day and one I will remember for quite a while. Well as long as we still have the green light tomorrow!

[Stoxs]

A local garden centre lost £10,000 of stock in the 2010 cold spell, a good proportion of that was very expensive Wollemi Pines. That was a disaster for the company.

Looking at the models, if we can believe the GFS output, and seeing the potential for severe frosts if it does, then a repeat may occur.

Poor management that isnt the weathers fault is it!!

like this time if you have £10.000 worth of stock that will die from frost cover it up or get it in side its not as if it hasnt been forecast is it!!!

[peterf]

A local garden centre lost £10,000 of stock in the 2010 cold spell, a good proportion of that was very expensive Wollemi Pines. That was a disaster for the company.

Looking at the models, if we can believe the GFS output, and seeing the potential for severe frosts if it does, then a repeat may occur.

that'll be down simply to bad crop management,always have a back up facility for expensive tender crops.regards Agriculture nothing will take much harm this time of year.

infact hard ground will be a blessing for slurry spreading.

[alan776600]

Can I please ask, If this erratic behaviour by gfs has now settled down and gone with the other models, could a scenario possibly be that the 00z and 06z could bring around even better charts as the gfs settles to the new course? Is that a good possibility or just a hopefull guess by myself? Thanks.

[georgiedre]

Well i for one am hoping for a slight adjutment west of the models which usually happens with gfs.(hopefully) again as it would mean more snow for us on the west coast. Do u guys think that it may move slightly west?

[Captain Shortwave]

Can I please ask, If this erratic behaviour by gfs has now settled down and gone with the other models, could a scenario possibly be that the 00z and 06z could bring around even better charts as the gfs settles to the new course? Is that a good possibility or just a hopefull guess by myself? Thanks.

Given the events in the strat, I wouldn't be too surprised if there are upgrades with respect to blocking to our north, what happens to us in respect to level of cold and chance of snow will vary a lot.

[Slowpoke]

Can I please ask, If this erratic behaviour by gfs has now settled down and gone with the other models, could a scenario possibly be that the 00z and 06z could bring around even better charts as the gfs settles to the new course? Is that a good possibility or just a hopefull guess by myself? Thanks.

'tis a guess at the moment... Anything beyond Monday is a guess.

Though, I personally believe taking all models into account and the GFS backtrack from today, cold + snowy into next week is more likely than the return of the Westerlies...

We shall see!

[DOdo]

Grrr typical lil ole Ireland not invited to the snowfest yet again :-( Models starting to show some (relatively) decent consistancy, so looking like you Brits will be in for a winner if the models verfiy and I'll be delighted for you all if it does! Us Poor Irish who missed out last Feb, may have to hope for a later shot at a deeper cold period towards the end of the month!

We have to see how things pan out before we can make judgements. GFS could backtrack.I wouldnt rule out plenty of snow from monday onwards Obviously things will modify nearer to the time. going by the ECM charts we could easily end up with a few streamers of our own.

[SMU]

Can I please ask, If this erratic behaviour by gfs has now settled down and gone with the other models, could a scenario possibly be that the 00z and 06z could bring around even better charts as the gfs settles to the new course? Is that a good possibility or just a hopefull guess by myself? Thanks.

(thanks Paul T)

its not 100% nailed, but if anything I would expect a couple more small corrective incriments WEST tomorrow-

The reason its so important is the upper air cold pool at 850 MB I keep going on about it - but in this scenario its around 200 miles diameter- but at the core will be -15c uppers-

http://modeles.meteociel.fr/modeles/gfs/runs/2013011018/gfs-0-114.png?18 just to the east of the UK-

The upper air cold pool very rarely reaches the UK- it usually pulls up short- heres a couple of exceptions

http://modeles.meteociel.fr/modeles/reana/1991/archives-1991-2-7-0-0.png

http://modeles.meteociel.fr/modeles/reana/2009/archives-2009-2-2-0-0.png

http://modeles.meteociel.fr/modeles/reana/1987/archives-1987-1-12-0-0.png

http://modeles.meteociel.fr/modeles/reana/1956/archives-1956-2-1-0-0.png

When this area stalls out & remains in situ the isobars relax & thats a grenade for low temps-

a classic low temp chart for the UK-

http://modeles.meteociel.fr/modeles/gem/runs/2013011012/gem-0-132.png?12

Fingers crossed ^^^^

S

[Slowpoke]

There is every chance of a significant, exceptional cold spell on the horizon, the building blocks are all there!. However, there is just as - at this stage - the chance of mild westerlies breaking in mid-week.

We'll know by the weekend

[alan776600]

Well im happy and thankful with your replies, Still trying to learn about the weather, been on this forum since just before the 2010 event and learnt alot already. With all models pointing towards this cold snap, I guess its just now guess work at how savere the snow will get. Is it 3am for the 00z model?

[alan776600]

(thanks Paul T)

its not 100% nailed, but if anything I would expect a couple more small corrective incriments WEST tomorrow-

The reason its so important is the upper air cold pool at 850 MB I keep going on about it - but in this scenario its around 200 miles diameter- but at the core will be -15c uppers-

http://modeles.meteo...fs-0-114.png?18 just to the east of the UK-

The upper air cold pool very rarely reaches the UK- it usually pulls up short- heres a couple of exceptions

http://modeles.meteo...991-2-7-0-0.png

http://modeles.meteo...009-2-2-0-0.png

http://modeles.meteo...87-1-12-0-0.png

http://modeles.meteo...956-2-1-0-0.png

When this area stalls out & remains in situ the isobars relax & thats a grenade for low temps-

a classic low temp chart for the UK-

http://modeles.meteo...em-0-132.png?12

Fingers crossed ^^^^

S

Will be amazing if that comes off and thank you Steve

[SandraD77]

of course its bad management, i take it you are management of this center?

If you cant keep expensive plants safe from frost then dont buy them, only take orders and sell only to order, or get some heating in there!!

OHHH not my fault!!!

tsk

typical uk nation wide , we never had tempeture in the last 5 years down to this so we will never ever again get tempeture down to this!

not snowed for 10 years so never ever going to snow again,

If we dont see snow before the mellenium we will never see it again int hsi country!!

Please kepp on topic as the mods have been stating all evening! Moaning and general chat threads exist to discuss your grievances re. garden centre managment! Thank you!

[BLAST FROM THE PAST]

Hi alan776600

We probably haven't got to the bottom of this yet, so yes further upgrades are very possible. Here's something I mused / updated in the seasonal thread 21/12/12 Mayan end of the world day

Posted 21/12/12

Prolonged and deep cold to takie hold as we deepen into January as the trough in Scandi becomes extension of HP from Greenland and a pronounced NE [generally] feed takes hold. The active pattern early Jan mayl be there but with deep cold knocking on doorstep it could get messy and much colder and snowier earlier than anticipated in LRF ie 8-10 Jan......dates, dates to watch another to watch 16-22 could be a large winter storm and a memorable part of winter.

Now the bit in bold is the main point here, I am actually now concerned about the potential here. I have used the word 'deluge' in other posts, we are looking at serious amounts of snowfall with set ups like these ansd at the surface its gonna be mighty cold. Date record cold temp challenges? I've touted this and with deep snowfields, cold uppers, slack winds...possible. Its all possible as we look at it right now.

The GFS as continued to move away from its zonal 'mess'......long may it continue, and I suspect it will.

Solar / lunar technique says yes. The MJO, Strat, GWO , AAM, GP [we are yet to get to the core of his cold outlook but build up looks on line], C, ECM, UKMO, GFS, GEM etc say yes...for now.

BFTP

Edited January 10, 2013 by BLAST FROM THE PAST