Model Output Discussion - 2nd March Onward

[sunnijim]

I usualy just lurk here and read with interest.I had to come out of the shadows on this one

I have often sat back quitely and considered the UKMO model as the one we always need on side for great winter synoptics from a cold/snow perspective,inside the reliable timeframe.

Generally this has been the case down the years,therefore i am stunned tonight that it has lurched toward the GFS solution at 72hrs!

Some sort of record surely? Thats the model that has been a laughing stock at times this winter with good reason.

Are we looking at a classic case of differant models modrlling differant parts better than others? Has the Gfs modeled things to our NW better in the past? ECM better at trends to our East.....

If anyone keeps a record it would be interesting.

[Frosty.]

Latest NAE develops the shortwave, so does the GME and the GFS.

Headline tonight could read UKMO humbled as shortwave drama puts the seal on a woeful week of modelling for the once star performer!

Those were the days

[Summer Sun]

At t120 now the high continues to sink south slowly but we remain under the coldest uppers we've had in a long time

[Snowman.]

Much better height in GL

[Harsh Climate]

I'm not seeing too much snow for eastern areas on a whole on the charts just yet. The window for convective snow showers from the east looks like only being around 48 hours (sunday-tuesday) and these windows nearly always shorten the nearer you get to the event.

.

After that we look like aquiring a more northerly flow, the troughs coming down in the flow will inevitably have milder sectors interspersed within them so good accumulating snow would then probably be restricted to higher ground apart from northern scotland.

I think the usual places like consett durham , parts of kent/east sussex , northern scotland could do quite well for heavy snowfall, but for the rest of us we still have a bit to go before we get those sledges back out. Especially given the time of the year.

Edited March 6, 2013 by Harsh Climate

[MR EXTREMES]

Much better height in GL

yep and it could well be a slight warm up but another blast looks to be lurking beyond t168

[Weathizard]

Still worried about that Azores high ridging in, doesn't want to give up does it! Think it could be a 2-3 day cold snap before that wretched thing gets in the way, if its going to be cold in march I want deep prolonged cold! Not asking much eh? Haha

[Snowman.]

Slowly getting there.

v

I'm not seeing too much snow for eastern areas on a whole on the charts just yet. The window for convective snow showers from the east looks like only being around 48 hours (sunday-tuesday) and these windows nearly always shorten the nearer you get to the event.

.

After that we look like aquiring a more northerly flow, the troughs coming down in the flow will inevitably have milder sectors interspersed within them so good accumulating snow would then probably be restricted to higher ground apart from northern scotland.

I think the usual places like consett durham , parts of kent/east sussex , northern scotland could do quite well for heavy snowfall, but for the rest of us we still have a bit to go before we get those sledges back out. Especially given the time of the year.

Essex?

Also the ECM still offers more.

[MR EXTREMES]

if i were to take the gfs at face value in fi then id say it screams reload from the ne now this could well turn out record breaking cold march.

[winterof79]

At t120 now the high continues to sink south slowly but we remain under the coldest uppers we've had in a long time

Central Northern England may be burried by this time next week.

http://modeles.meteociel.fr/modeles/gfs/runs/2013030612/gfsnh-0-114.png?12

UKMO has the preferred METO slower evolution..... if at all http://modeles.meteociel.fr/modeles/gfs/runs/2013030612/gfsnh-0-114.png?12

[LomondSnowstorm]

I'm not seeing too much snow for eastern areas on a whole on the charts just yet. The window for convective snow showers from the east looks like only being around 48 hours (sunday-tuesday) and these windows nearly always shorten the nearer you get to the event.

.

After that we look like aquiring a more northerly flow, the troughs coming down in the flow will inevitably have milder sectors interspersed within them so good accumulating snow would then probably be restricted to higher ground apart from northern scotland.

I think the usual places like consett durham , parts of kent/east sussex , northern scotland could do quite well for heavy snowfall, but for the rest of us we still have a bit to go before we get those sledges back out. Especially given the time of the year.

Yes, well other than the -12/-14C uppers and 36-48 hours of easterly winds accompanying them, along with the potential for a prolonged cold spell following from the northeast, it is a little bit underwhelming....

Edited March 6, 2013 by LomondSnowstorm

[SMU]

^{http://modeles.meteociel.fr/modeles/}gfs^{/runs/2013030612/}gfs^{-1-156.png?12}

GFS ^{going for the second bite which could be as good as the first- without the immeadiate sinker!}

[snowhope]

If this does come to fruition, is any snow that falls likely to melt with the given day time temperatures and the strength of the sun this time of year or would it stay throughout the cold snap?

[winterof79]

I'm not seeing too much snow for eastern areas on a whole on the charts just yet. The window for convective snow showers from the east looks like only being around 48 hours (sunday-tuesday) and these windows nearly always shorten the nearer you get to the event.

.

After that we look like aquiring a more northerly flow, the troughs coming down in the flow will inevitably have milder sectors interspersed within them so good accumulating snow would then probably be restricted to higher ground apart from northern scotland.

I think the usual places like consett durham , parts of kent/east sussex , northern scotland could do quite well for heavy snowfall, but for the rest of us we still have a bit to go before we get those sledges back out. Especially given the time of the year.

According to the GFS output which is too quick.I can still see copious heavy snow showers in an unstable very cold flow.

http://modeles.meteociel.fr/modeles/gfs/runs/2013030612/gfs-2-120.png?12

Not interseted in the "this time of year " theory with uppers of this magnitude

http://modeles.meteociel.fr/modeles/gfs/runs/2013030612/gfs-1-114.png?12

[Thundery wintry showers]

If the GFS comes off (a big "if") then any snow cover that accumulates on Sunday/Monday should stick around if it reaches a depth of over an inch, but a thin covering will probably still thaw in the sun, for a patchy thin snow cover is less effective at reflecting solar radiation. A widespread daytime thaw would then be likely on Tuesday as less cold air is projected to move down from the north.

The UKMO has brought another possible scenario to the table as it projects the high sinking south-eastwards rather than southwards and that helps to cut off the easterly flow as the cold air arrives, meaning not many snow showers, so while a cold spell now looks very probable, a snowy one is still a long way from being "nailed" as a few posts have been suggesting.

The reason why easterlies and north-easterlies are statistically more likely to produce grey drizzly weather as we head through the season is increasing moderation of low temperatures and heights in the upper atmosphere, combined with a cold North Sea, but the airmass projected to reach us is very cold at upper levels and with fairly low 500hPa heights so in theory it should not be significantly less conducive to a "sunshine mixed with heavy snow showers" sort of regime than it would be in January.

Edited March 6, 2013 by Thundery wintry showers

[Harsh Climate]

According to the GFS output which is too quick.I can still see copious heavy snow showers in an unstable very cold flow.

http://modeles.meteo...fs-2-120.png?12

Not interseted in the "this time of year " theory with uppers of this magnitude

http://modeles.meteo...fs-1-114.png?12

Absolutly, with the depth of cold between sunday and tuesday it doesn't matter what time of year it is.

BUT after then, in a northerly/north easterly without the extremely cold uppers the time of year then really does come into play. It could be the difference between snow that settles on low ground and snow that doesn't.

[LomondSnowstorm]

If you find it underwhelming, I suggest you get a new hobby

I for one will be enjoying this cold spell as it's unusual we get uppers as low as -14.

But do -14 uppers = snow??? Certainly not, thought you would know better but nethermind.

They equal anything that falls out of the sky being snow certainly, though of course not necessarily automatically snow. WIth an easterly wind though and low heights preceeding it I would think that the potential for snow is certainly much greater than most other cold spells in March of the last 20-30 years for most of the UK.

[winterof79]

Our last attempt at an Easterly was an entirely different setup with a dry flow for many.

http://modeles.meteo...3022300-0-6.png

http://modeles.meteociel.fr/modeles/gfs/archives/gfsnh-2013022300-0-6.png

I know we cannot predict anything at this range too.

This time may be much better

http://modeles.meteociel.fr/modeles/gfs/runs/2013030612/gfs-0-114.png?12 and that is the progressive run...

Edited March 6, 2013 by winterof79

[bluearmy]

^{http://modeles.meteo...fs-1-156.png?12}

GFS ^{going for the second bite which could be as good as the first- without the immeadiate sinker!}

you mentioned this yesterday steve and it does begin to look as thought the models are clustering around this solution. initial surge of very low uppers with a less cold push down from the north followed by a second push sw of the low heights from the ne. in dec/jan, that middle period of less cold uppers would still deliver frontal snowfall but in mid march, will be much less likely.

[Frosty.]

Models today are looking stunning for a very potent cold blast next week, the gfs is probably still wrong with the high with it's eastwards bias, if the ecm 12z follows the path of the 00z we should be looking at something along the lines of today's ultra wintry 6-15 day update.

Edited March 6, 2013 by Paul

[Snowman.]

UKMO still on its own at 144.

BUT made some progress.

Lol you must laugh at GFS logic

This

To this

Edited March 6, 2013 by SN0WM4N

[weather eater]

UKMO has shifted it was not a cert but always likely, 12z GFS looking very impressive, shame it’s taken us until March to develop a proper GH, that’s if it comes off of course. Hopefully we will be able to put to bed the notion that the sun is too strong for serious cold and snow in March.

Edited March 6, 2013 by weather eater

[Frosty.]

UKMO has shifted it was not a cert but always likely, 12z GFS looking very impressive, shame it’s taken us until March to develop a proper GH, that’s if it comes off of course. Hopefully we will be able to put to bed the notion that the sun is too strong for serious cold and snow in March.

I really don't think it is a shame weather eater, the arctic is currently much colder than average, the north sea is colder than average, by mid march, inland convection increases rapidly so the showers can develop more widely inland and not just hug the coastlines around the uk. Next week could be one for the books, very special indeed for the time of year, very impressive even by mid winter standards actually. especially considering how severe the latest meto update is, another upgrade since yesterday even.

Edited March 6, 2013 by Frosty039

[Coast]

Maybe a good time to remind people that if your submission has little or no content or discussion regarding the current output of the models and subsequent analysis, but it is a comment on the emotion or general 'feeling' about the weather you think is coming, here is the place for those posts:

[mushymanrob]

Latest NAE develops the shortwave, so does the GME and the GFS.

Headline tonight could read UKMO humbled as shortwave drama puts the seal on a woeful week of modelling for the once star performer!

tbh nick im not so sure anyone can write off the ukmo output. its current suggestion that there will be no northeasterly with extremely cold uppers ala the gfs, might yet become reality. and dont forget that the other models go out much further, so the expected cold has only just become visible on the ukmo output.

the ukmo still insists on a ridge blocking off the worst of the cold, not what most here want to see as itll rob them of the intense cold . but as i see it, the ukmo output is just as vallied as the ecm or gfs, dispite lack of support from the ensembles. its a very plausable evolution, dont write it off too quickly, theres plenty of time for adjustments from any model.

, i seem to recall lying snow for over a week even though it only fell one day and the rest was variable cloud.

ive never seen 7 days of lying snow in march, 4 in 1970 is the most. but i guess locations are different.

When the Met is talking about disruptive snow and a mild lover like mushymanrob concedes defeat and admits there will be a record breaking cold snap it is going to take an extraordinary act of god to stop it happening now

thats not what i said. theres a possibility of some records being broken IF something like the current gfs come into reality, i didnt say there WILL be record breaking cold.... i do believe though that we will get a noticable cold spell, theres no milder option on the table just, below average, cold, very cold, or very very cold!

even if the ukmo proves to be right, its not a mild run, and its suggesting a slower cold evolution, not as bad as the gfs or some ecm's (which will probably depict spaish plumes tonight, its so inconsistent :lol: ) but cold nontheless.