Winter Model Output Discussion 01/02/2013 12z onwards

[Ladyofthestorm]

Done

I saw it and thankyou frosty...bug hugs, very similar to the baby approaching our shores, me just has that feeling something bigis on the way!

[cyclonic happiness]

Wishbone damn, snowless for many inland locations

Not always, i remember in the 80's troughs coming down from the north?

[bryan629]

Not always, i remember in the 80's troughs coming down from the north?

so do i , especially dec 2010

[I remember Atlantic 252]

Not always, i remember in the 80's troughs coming down from the north?

but no trough showing on that particular FAX chart, but yes they can

[lorenzo]

Tight clustering sums it up SK, only one cluster within those postage stamps this evening, don't see that often, well not that have noticed. Makes a change from the 6/7 on offer at peak of entropy carnage.

Interesting thoughts on the Winter so far Steve, a good read and I think expectations, awareness and excitement were all indeed lifted in November period simultaneously, and if you look back on the thread at that time rightly so.

The academic content of many of the papers is heavy going and many I have read concern pre-cursors to the warming events vs a quantity of analysis on propagation, the papers going for it forensically in this regard comparing one or two events across the entire vortex spectrum for changes on each isentrope rather than the series of events. Martineau is on the case.. will certainly be keeping an eye out for more propagation papers to lift understanding there.

wrt HLBs I think folk were picking up on the Cohen climatology and running with this as a given, it certainly pointed towards the Greenland area and naturally looking there for a trop. response, one demised by the Canadian Vortex Segment. I think it is fair to say the SSW changed the pattern and many benefited from this in terms of some good proper Winter, granted perhaps not as spectacularly as what was expected, nonetheless it happened and with it SSWs went mainstream which can only enhance future understanding. I think the backdrop of 2009 2010 also still distorts expectations from time to time.

Other questions this Winter for me concern the MJO analogs being bashed around by migrating vortex chunks and also the GFS continued fail is well of note, I think you were being kind calling it useless earlier. The UKMO model has had a great season and enhanced it's reputation, coupled with some great input from Ian F, was good to see less Met Office bashing than previous yrs. All in I think a hefty degree of wariness in NWP output I think was instigated / re-ignited in everyone after that ECM flip.

Been a fascinating contrast at times between the close up technical synoptic insight you provide and watching the longer lead background changes of the SSW / GWO, both I believe are equally as important for our understanding of where our Winter can lead.

[Tim Bland]

but no trough showing on that particular FAX chart, but yes they can

If you look at the faxes http://www.meteociel.fr/modeles/ukmo2.php?carte=2000&ech=0

At 96 hrs the cold front is north of Scotland at 120 hrs it has cleared the south coast. So whilst there's no troughs showing if there were a 108hr fax it would have it in the middle of the uk.

[Panayiotis]

Initiation of Scandi high at 228hrs?

240hrs and its getting there......

Edited February 1, 2013 by Panayiotis

[snowking]

Not always, i remember in the 80's troughs coming down from the north?

Similar to late jan 03 and 04

http://www.wetterzentrale.de/pics/archive/ra/2003/Rrea00120030130.gif

http://www.wetterzentrale.de/pics/archive/ra/2004/Rrea00120040128.gif

03 saw the M11 brought to a standstill due to an unexpected snowfall during Thursday evening's rush hour

04 was the infamous thundersnow event - some very heavy snowfall rates that day!

Such a flow is always prone to unexpected disturbances

SK

[Panayiotis]

Ha GFS gets there at 312hrs!..... Fi is beautiful on the GFS 18z, matching the ECM.

Now thats a chart......

Edited February 1, 2013 by Panayiotis

[Tamara]

"I think it's coming anyway, and this storm on Tuesday is the pattern changer much as there was a severe windstorm around 1 Feb 1969 although that was more of a straight northerly blast."

Interesting re. Rogers thoughts about a possible evolution similar to Feb.1969.

Tomorrows ECM chart at 12z - http://www.wetterzen...ics/Recm241.gif

3rd Feb 1969 - http://www.wetterzen...00119690203.gif

Forecast chart for 6th Feb - http://www.wetterzen...cs/Recm1201.gif

8th Feb 1969 - http://www.wetterzen...00119690208.gif

Forecast chart 8th Feb - http://www.wetterzen...cs/Recm1681.gif

10th Feb 1969 - http://www.wetterzen...00119690210.gif

You can see some similarities between the poss. evolution this Feb and what actually occurred in 1969.

The obvious difference being the lower heights and segment of the PV west of Greenland.

IF this segment were to weaken as we move into the 2nd week of February, its not out the question to see a similar

scenario developing, poss. SE diving low and Russian high waiting to pounce and trundle into Scandinavia.

I'll leave you with a little look further into that Feb. of 1969.

http://www.wetterzen...00119690213.gif

http://www.wetterzen...00119690215.gif

http://www.wetterzen...00119690219.gif

Weather Gods, make it so!

Regards,

Tom.

Glass half full it is then

[Panayiotis]

Is everyone speechless by the GFS 18z or does no one like cold and snow?!

Edited February 1, 2013 by Panayiotis

[Tim Bland]

Model fatigue has definitely set in when there's no response from an 18z like that! Great to see the GFS climbing onboard with the ECM Lets hope it's a seamless week ahead with all models starting to agree.. Not to much to ask is it?

Edited February 1, 2013 by Tim Bland

[Yarmy]

Most things I can deduce, but 'wishbone'? Definition anyone, please? (BTW, don't google it for the love of God. There are things in this world of which it is best to be ignorant. :-o )

[I remember Atlantic 252]

Is everyone speechless by the GFS 18z or does no one like cold and snow?!

Too FI for me to be excited

[Grimsby Snow Lover]

I think it is safe to say that the Atlantic is pretty dead in FI on this run lol

http://www.wetterzentrale.de/pics/Rtavn3601.png

[bluearmy]

Is everyone speechless by the GFS 18z or does no one like cold and snow?!

Not really - if we accpt that gfs low res is purely for entertainment value then it it thus, whether cold or mild.

[J10]

Wishbone effect = showers over coasts, but dry inland.

By the way own up, who let Roger J Smith the keys to the GFS 18Hz tonight.

[Penrith Snow]

Snowking the ensembles on the ECM that are flat & against the pattern are distorting the mean flatter & further east.

Take the outliers out & watch that high rise up!-

the ECM 240 is excellent considering the opposing runs....

S

Agreed Steve,

We have to be very careful looking at ENS Means, I always prefer to concentrate on the Op which afterall is the 'real' run.

IMO the ECM shows loads of potential and I think the MetO are undercooking the next 5-10days particularly in the North West.

I remember 3rd February 2003 which is a carbon copy of the +96 and the MetO were forecasting snow on hills yet in the NW snow was falling down to sea level accumulating to depth of 10cms just a few miles inland.

http://www.wetterzentrale.de/archive/2003/brack/bracka20030203.gif

It might not happen but you can not deny the potential in tonights ECM run.

Andy

[bryan629]

HI Yarmy,

wishbone means , where a trough or a band of showers approach from the north, they penetrate northern scotland and die out as they haed inland towards the scottish mountains.

either side of the trough or band of showers east or west, keep their energy as they miss the land and travel down the east and west coast, their energy is kept up because of convective energy from the warm waer below them , until they hit land around our east or west coast, such as north yorkshire, the cheshire gap, north wales and east anglia .

[Yarmy]

Wishbone effect = showers over coasts, but dry inland.

By the way own up, who let Roger J Smith the keys to the GFS 18Hz tonight.

Thanks. Outside chance IMBY from the Northerly then, I suppose.

[john pike]

note the weather front on the tuesday fax just over scotland

see it has cleared the south on the wednesday fax

its the bit in between we need to see

Edited February 1, 2013 by john pike

[Tom Montalbano]

Glass half full it is then

Hi Tamara,

Yes, I change....like the weather!

All joking aside, emotions swinging with the models but the way things are shaping up expect the UK to be the war zone for the final big battle of the campaign!

Versus

Vortex v. The Bear

Regards,

Tom

Edited February 1, 2013 by TomSE20

[Richie V]

This looks exceptionally promising for severe cold by the middle third of February.

The dive-bombing low on Tuesday will turn into a wintry hurricane for northern regions of the UK and in itself is a major severe weather event, but after a couple of days it will reach a position over central Europe that will allow a retrograde cycle just showing signs of life now to develop gradually and feed the coldest Siberian air west across northern Russia into Scandinavia.

I think there will be near-record cold in mid-February and that means daily means in the -5 to -10 C range, so a very severe frost and with a northeast flow there may be heavy snowfalls even without any organized low pressure, but this winter also has shown a tendency to storminess so I have the feeling once this very cold air starts moving in, there could be epic snowfalls with it.

The eastern Canadian vortex from my research can be expected to last about a week then start to drift northwest to become another part of the hemispheric retrograde cycle. Heights will then build over central-eastern North America and they could go from the current cold pattern to very mild in about ten days to two weeks.

I think it's coming anyway, and this storm on Tuesday is the pattern changer much as there was a severe windstorm around 1 Feb 1969 although that was more of a straight northerly blast. But the temperature signal from very mild to very cold is similar, and don't forget that also happened (a bit earlier in late January) in 1947.

Thats one hell of a bold post, hope you are right, there are lurkers from the daily express a d daily mail in here you know. Cant wait to see the express take on this on sunday... "violent artic hurricane to cripple uk" i'm certainly not dbouting your skills but I sure hope your on the money with this one!!!!

I respect you massively dude, best of luck.

You know, Ian McCaskill once said it will be breezy up the channel!!!

Ric

[TEITS]

I don't wish to ruin the positive vibe on here but afterI read RJS post and I have to say it was rather OTT and for a minute I thought was reading one of Piers Corbyn forecasts.

A wintry hurricane on Tuesday isn't being suggested. What we have is your typical deep Atlantic LP that will bring strong winds and temporary blizzard conditions to the mountains of Scotland but for the majority of us a typical wintry showers along coastal districts.

As for record breaking cold occuring after the N,ly and this is again rather OTT. We are seeing the models trend in the right direction and snowfalls occuring via systems tracking SE from the NW remain a strong possibility. However whether we see significant blocking to our NE develop with bitter upper temps of -15C remains to be seen.

[Jason M]

Personally I'm underwhelmed by the pub run. The ensembles currently rolling out look a huge upgrade to me though.

In the 5-8 day range I'd expect the opp to be one of the milder runs.

Jason