Winter Model Discussion 18Z 19/2/13 onwards.

[johnholmes]

Why do folk have to use the word streamer?

Why not as Ian suggested the correct term, be it Thames estuary convection, Cheshire gap, Bristol Channel, Wash or wherever. This satisfies two things, it is metorological correct and it explains without the discussion we have seen tonight on just what is a such and such streamer.

[TEITS]

Why do folk have to use the word streamer?

Why not as Ian suggested the correct term, be it Thames estuary convection, Cheshire gap, Bristol Channel, Wash or wherever. This satisfies two things, it is metorological correct and it explains without the discussion we have seen tonight on just what is a such and such streamer.

Simple look below and you will see why they are referred to as streamers!

http://en.wikipedia.org/wiki/File:Snowband_anim.gif

[Bonjangle]

Pemboke Dangler !!! no mention of my Dangler .... Shooosh

[swfc]

We had a sheffield shooter in 2010!cant see us getting another tho in my lifetime

[Roger J Smith]

My guess remains heavy snow in Kent with that 20-30 cm estimate still on the table. I think the depth and fetch issues will overcome any stability (from my experience with Great Lakes snow, east winds don't need to combine with much instability, just getting cold enough air over the water seems to be a good start). That should accumulate over three days by the way but Friday night and Saturday look best.

[london-snow]

My guess remains heavy snow in Kent with that 20-30 cm estimate still on the table. I think the depth and fetch issues will overcome any stability (from my experience with Great Lakes snow, east winds don't need to combine with much instability, just getting cold enough air over the water seems to be a good start). That should accumulate over three days by the way but Friday night and Saturday look best.

& what about london rjs while your at it mate any predictions?

Edited February 20, 2013 by london-snow

[swfc]

My guess remains heavy snow in Kent with that 20-30 cm estimate still on the table. I think the depth and fetch issues will overcome any stability (from my experience with Great Lakes snow, east winds don't need to combine with much instability, just getting cold enough air over the water seems to be a good start). That should accumulate over three days by the way but Friday night and Saturday look best.

you jest surly

[london-snow]

you jest surly

Well the man has spoken & unlike a lot of us here he has no need to ramp as he resides far away + I love his lrf's and he is normally not that far off the mark along with my friend fred.

[swfc]

Well the man has spoken & unlike a lot of us here he has no need to ramp as he resides far away + I love his lrf's and he is normally not that far off the mark along with my friend fred.

ok!i stand corrected and await the end of the world down south yet again!!

[london-snow]

ok!i stand corrected and await the end of the world down south yet again!!

LOL i wish (snow wise of course) but doubt we will see that much.

Come on rjs be spot on this time mate lol.

[Zenarcher]

Models seem confident on a fine spell of weather for the next 7 days, high pressure in charge, mainly dry with plenty of sunshine but temperatures on the cold side with overnight frosts.

[Ian Brown]

My guess remains heavy snow in Kent with that 20-30 cm estimate still on the table. I think the depth and fetch issues will overcome any stability (from my experience with Great Lakes snow, east winds don't need to combine with much instability, just getting cold enough air over the water seems to be a good start). That should accumulate over three days by the way but Friday night and Saturday look best.

With respect Roger there is nothing to suggest anything like that. If anyone can show me an archive where anywhere in the UK has received between 8 and 12 inches of snow with the core of HP located so near to Scotland then I will happily review.

[winterof79]

Now that is an interesting run.Escpecially from 168z

http://www.meteociel...map=1&archive=0

Where is our high going to end up.IF it shifts n/w there will be an almighty cold beginning to March.

Somethings brewing http://www.wetterzentrale.de/pics/MT8_Manchester_ens.png

Edited February 20, 2013 by winterof79

[winterof79]

The interest begins around the 28th on the ensembles

http://www.wetterzentrale.de/pics/MT8_Manchester_ens.png

The control shifts the high n/w and allows an arctic plunge of epic proportion and takes a few members with it.

http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=192&mode=0&carte=1

The operational thinks about following but takes its time to get there.

ECM takes the high on its holiday n/w too.

[weather eater]

ECM is a very good run and 240h shouts Greenland high. ECM cold next week with high pressure over us but most will be happy with that 240 chart. Actually it maybe West Greenland its heading for but i'm not sure... GEM is also keen...

The only problem with any Greenland high is we don't want it to far West... Heights in Europe will be a big problem with to much SW/W to our weather. We would need the high in Europe to sink far enough south and the Greenland High further east the better... I dunno.

The long term guidance is for a west Based NAO, the GFS operational’s have been backing that idea for several days now and the 240hr ECM chart is now pointing that way as well, a long way to go but that solution looks odds on now, I wonder if the GFS will get credit for picking it up at that range.

[Jason M]

Well looks like there will be some snow around this weekend after all. No massive amounts but some places in the south could get a good few cms.

It looks to me that a Greenland high and west based -NAO are now nailed on for 7-10 days time. How can I be sure? Sod's law of course!

Jason

[bluearmy]

If a west based -NAO verifies, it will be a rare occasion this winter where gfs op has been in agreement with its extended ens in low res.

When I went with this option for the end of feb/beginning march it was generally the gfs op that was showing this solution +naefs. Since then, things have shifted somewhat such that the block hangs on longer (not unexpected) and we see a split opening up in the nwp between west based neg nao delivering a wsw regime and more centrally based neg nao bringing a threat of more cold to nw europe. Odds still support the former but if the polar profile adjusts a little, the latter would be there in a flash.

[TEITS]

So the ECM now follows the GFS 18Z, otherwise known as the pub run, which I hasten to add suggested the same on the previous night. If I lived in Scotland/N England I would be very excited at the potential from these runs but further S it would remain uncertain how far S the much colder arctic blast would penetrate.

Some crazy cold ensembles being shown with -15C for March. I would wonder what the record is for the coldest upper temps in March.

http://cdn.nwstatic....bridgeshire.png

Back to the E,ly and im still annoyed at this has downgraded over many days. Still remains a chance that locations such as E Anglia/SE could see a few cm on Saturday and maybe slightly more if some lucky location sees a constant band of light snow. Absolutely no chance of 20-30cm being recorded. The pressure is too high, time of year all go against such snowfalls. This is why Dec 2010 was such a special cold spell and why locations such as Lincs recorded 45cm of snow. We had very cold upper temps spreading across a relatively warm sea with HP being further N. Don't forget the N Sea is much warmer in early Dec compared to late Feb.

Edited February 20, 2013 by THE EYE IN THE SKY

[fergieweather]

Absolutely no chance of 20-30cm being recorded. The pressure is too high, time of year all go against such snowfalls. This is why Dec 2010 was such a special cold spell and why locations such as Lincs recorded 45cm of snow. We had very cold upper temps spreading across a relatively warm sea with HP being further N. Don't forget the N Sea is much warmer in early Dec compared to late Feb.

Yup, no idea how this 30cm notion appeared on here but it's DailyExpresseology (aka Maddenology), not Meteorology.

[Severe Siberian icy blast]

Well this morning we have seen a shift in the gfs ensembles away from milder weather along with the ECM operational beginning to hint at maybe a northerly wind flow, by no means is anything guaranteed but there is something been picked up by the models .

It's no supprise to see the warmth that the models picked up on from the high been watered down considerably , it's likely the models over reacted to a signal they picked upon ,how many times do we see this with cold weather as it comes into the reliable time frame.

What's interesting is the obvious shift in the gfs ens , certain members including the mean going very cold again.

[ANYWEATHER]

So the ECM now follows the GFS 18Z, otherwise known as the pub run, which I hasten to add suggested the same on the previous night. If I lived in Scotland/N England I would be very excited at the potential from these runs but further S it would remain uncertain how far S the much colder arctic blast would penetrate.

Some crazy cold ensembles being shown with -15C for March. I would wonder what the record is for the coldest upper temps in March.

http://cdn.nwstatic....bridgeshire.png

Back to the E,ly and im still annoyed at this has downgraded over many days. Still remains a chance that locations such as E Anglia/SE could see a few cm on Saturday and maybe slightly more if some lucky location sees a constant band of light snow. Absolutely no chance of 20-30cm being recorded. The pressure is too high, time of year all go against such snowfalls. This is why Dec 2010 was such a special cold spell and why locations such as Lincs recorded 45cm of snow. We had very cold upper temps spreading across a relatively warm sea with HP being further N. Don't forget the N Sea is much warmer in early Dec compared to late Feb.

Well as virtually always the Easterly is downgraded, no surprise tbh! But certainly a chunck of very cold air moving across the southern half of the Uk, as been said ,no deluge of snow but a few flurries blowing about in the wind over the next several days...

[I remember Atlantic 252]

With respect Roger there is nothing to suggest anything like that. If anyone can show me an archive where anywhere in the UK has received between 8 and 12 inches of snow with the core of HP located so near to Scotland then I will happily review.

Agree with Roger, Kent is in for a snowfest, (certain parts) maybe not 30cms, but certainly 15-20cms fri to sun night, then thaw monday

[phil nw.]

The medium term starting to look interesting and indicating that the block is going nowhere fast and could well maintain a colder outlook for the UK.

Upstream at t168hrs on both Operationals show a good example of the jet splitting off the eastern seaboard.

http://modeles.meteo...snh-0-168.png?0

http://www.meteociel...1-168.GIF?20-12

this sends enough energy into the southern jet which keeps those low heights in S.Europe holding the block from sinking.

With the bulk of the vortex draining across to Siberia this leaves those +ve height anomalies to the NW.

As the later ECM shows it keeps the possibilty of a height build to the NW open but it`s too far away at this stage to see whether it will favour the UK.

http://www.meteociel...1-240.GIF?20-12

Early March though starting to look colder than previously thought as our surface cold hangs around next week and hints that an Arctic incursion already modeled further east may become an option nearer home.

Edited February 20, 2013 by phil nw.

[Tim Bland]

Gefs Control run worth a look this morning, if only for entertainment. Shows what is possible...

http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=348&mode=0&carte=0

Love Ian's post .. "Maddenology" it has a better ring than "Corbynology". If anywhere receives a level 30cm this weekend I'll run through it naked for 24hrs

Edited February 20, 2013 by Tim Bland

[Methuselah]

As we approach the equinox, it might actually happen: this winter's ever-present 'retrogression signal' might actually lead to something...A 1975-like Spring, perhaps?