Winter Model Discussion 12Z 15/02/13 onwards.

[Ian Brown]

12z UKMO T+144: http://www.meteociel...44-21.GIF?15-17

Paving the way for an Arctic blast further down the line?

Core of heights closer to Scotland, hard to judge where it is going from there.

Good consistency from the GFS !

[Radiating Dendrite]

GFS from t180 to t216 would give huge amounts of snow. Love the GFS! ,

Not on the south coast though.

Midlands northwards.

[Severe Siberian icy blast]

12z UKMO T+144:

Paving the way for an Arctic blast further down the line?

Excellent chart that is , some very very deep uppers making there way down the eastern flank of the high ready to inject the high potentially and push west, then we have the low down toward Iberia punching north , I think if we saw the 168 chart , the isobars on the high will begin to squeeze together and give us a strong easterly . Like Steve M eluded to earlier .

[Mucka]

Yup, I'm really liking the UKMO which is close to this mornings but with being 12h advanced shows good signs of retrogression and that vigorous trough digging down the Eastern flank would be ideal in that it prevents the high being pushed East and encourages the high to get squeezed North with the Atlantic undercutting.

[Tamara]

At t44 UKMO would be sublime if the High was a fraction further North - but there looks to be a possible evolution to a slippery sliding snaking low from the south west as the High maybe transfers west and low pressure undercuts

Edited February 15, 2013 by Tamara Road

[Cheshire Freeze]

As GFS FI shows, we need to try and manouvre away from a west based -NAO, otherwise we'll be having a taste of spring before Feb is out!

[That ECM]

Not on the south coast though.

Midlands northwards.

Have another look. South coast prob not but certainly not midlands north.

[Radiating Dendrite]

Yup, I'm really liking the UKMO which is close to this mornings but with being 12h advanced shows good signs of retrogression and that vigorous trough digging down the Eastern flank would be ideal in that it prevents the high being pushed East and encourages the high to get squeezed North with the Atlantic undercutting.

All I see in that chart is a high which needs to be 300-400 miles north to give us anything.

All the cold is pouring into France.

I know it will change, but some on here really do seem to have the snow goggles on!

[Met4Cast]

Yep the GFS is suddenly showing what we want so it's back to being the model of choice, excellent, welcome back GFS! *facepalm*

GFS seems to be very much on it's own with regards to the undercut bringing snow across Southern parts. The UKMO and to some extent the ECM are having none of it. I suspect the GFS is underestimating the Northern extent, expect to see shifts Southward as the pattern comes closer to the reliable.

[Severe Siberian icy blast]

GFS in the far reaches of high res has this, I sense an epic Fi, all eye candy though!

That chart fits the bill perfectly with what the anomaly charts are showing from the NAFFS

[snowking]

Hmmmm...

I wonder where I might have seen that before:

SK

Not on the south coast though.

Midlands northwards.

Think -1c 850 isotherm as the snow/rain boundary in a situation such as this under low heights

SK

Edited February 15, 2013 by snowking

[Severe Siberian icy blast]

Hmmmm...

I wonder where I might have seen that before:

SK

Think -1c 850 isotherm as the snow/rain boundary in a situation such as this under low heights

SK

Agree entirely

[Harsh Climate]

I will get excited when I see charts like this

Compare that to this potential easterly

Doesn't look as good now does it..

Edited February 15, 2013 by Harsh Climate

[bluearmy]

Low res delivers another west based -NAO. thats becoming a strong theme and if stewart has nothing to offer re telecons saying anything different then one would be inclined to agree with this evolution. the low res output may be a bit progressive in this regard.

[Mucka]

All I see in that chart is a high which needs to be 300-400 miles north to give us anything.

All the cold is pouring into France.

I know it will change, but some on here really do seem to have the snow goggles on!

Well the weather doesn't stand still like a single chart - it is all about the progression of the pattern and that progression clearly shows the high beginning to retrogress from 120h to 144h with a trough digging down the Eastern flank and the Atlantic undercutting.

Also I didn't mention anything about snow since that chart does not show copious snow fall, what it does show is a cold pattern setting up where snowfall chances would increase dramatically as the high retrogresses and the Atlantic undercuts and that is before thinking about the possibilities from the NE as the pattern gets backed West.

Massive potential for wintry goodness.

Edited February 15, 2013 by Mucka

[Radiating Dendrite]

A word of caution though.

Was the GFS not showing all these charts back in Jan at this sort of time frame?

As others have said, the turnaround from some on here is incredible. As soon as a model starts to show a solution they like it is welcomed back and hailed as being great

[mcweather]

Not on the south coast though.

Midlands northwards.

Blizzard of 18/19th february1978 gave mountains of snow on the south coast of Dorset with uppers of minus 2C ! With such low pressure and a continental feed you don't need minus of 10 uppers for snow.

Edit I see snow king beat me to it.

[mcweather]

I will get excited when I see charts like this

Compare that to this potential easterly

Doesn't look as good now does it..

Well you won't get excited very often then HC

[Radiating Dendrite]

Blizzard of 18/19th february1978 gave mountains of snow on the south coast of Dorset with uppers of minus 2C ! With such low pressure and a continental feed you don't need minus of 10 uppers for snow.

Edit I see snow king beat me to it.

Yes I know that.

[Tim Bland]

Low res delivers another west based -NAO. thats becoming a strong theme and if stewart has nothing to offer re telecons saying anything different then one would be inclined to agree with this evolution. the low res output may be a bit progressive in this regard.

Fits well with the Meto outlook for temps to recover into March and snippets from Ian F. IMO next weekend / last week of Feb is the last chance saloon for a proper dump of snow. After that then a west based NAO looks odds on.

[snowking]

A word of caution though.

Was the GFS not showing all these charts back in Jan at this sort of time frame?

As others have said, the turnaround from some on here is incredible. As soon as a model starts to show a solution they like it is welcomed back and hailed as being great

RD

I get where you are coming from, but we have been working on the basis that the GFS has been an outlier synoptic solution for the past few days (which it has been!)

It is now more reflective of the H500 ensemble mean patterns that have been suggested by its own, and other, ensemble suites for some time now

SK

[Harsh Climate]

Well you won't get excited very often then HC

I know that's why I intend on moving to a different country later in life, this one sucks for deep quality snow.

[Severe Siberian icy blast]

Just take a moment hypertheticaly to say the ukmo did happen .

At 120 look at the low toward Iberia , and the angle of the tilt on our high

Then have a look where the low goes at 144 , it moves northeast , with the very cold upper air on the eastern flank of the high moving south

The next chart would see the our high tilt giving us a strong northeasterly air flow , with disturbances ejecting toward the uk over the North Sea , at the same dragging in them bitter cold uppers from the east , given the angle of the high and winds from the northeast them uppers will make a b-line for Britain .

All very interesting and not for minute suggesting that will be the case but be interesting to see where future runs take us

[chris55]

A word of caution though.

Was the GFS not showing all these charts back in Jan at this sort of time frame?

As others have said, the turnaround from some on here is incredible. As soon as a model starts to show a solution they like it is welcomed back and hailed as being great

It's called getting model consensus. Now all three agree on the broad pattern we can look at the mid range again from all models with similar confidence (or not). GFS was way out on a limb with it's known weakness's and had the pattern wrong, now it has the initial pattern in sink with the UKMO and ECM we can trust it again, it's simple really.

[SMU]

The GFS is FAR FAR to fast tonight with its solution, it piles up the energy to the SW & pushes through.

The UKMO & GEM are in tandem tonight with PERFECT positioning of lows to force the cold over the UK- The GEM just edging the UKMo by 200 miles north-

http://modeles.meteo...em-0-138.png?12

http://www.meteociel...44-21.GIF?15-17

Remember my 4 ingredients this morning-

Iberian Energy, Southerly jet, High pressure location, upper air cold pool-

GEM has all 4, UKMO has 3 - just lacking the depth to the upper air cold pool-

However everything is perfectly alligned energy wise for the high to lift a little a energy piles in from the SW, the SE ( from iberia ) & the NE over Scandi.

Very confident of this signal now for very cold air at day 5- with surface temps for england sub 2c on the UKMo 120- but more particular 144.

http://modeles.meteo...em-0-144.png?12 GEM CLASSIC

http://modeles.meteo...0-156.png?15-17 NAVGEM Awsome

Just would have preferred the UKMO to be the best--- never mind.

discount the GFS tonight- its WAYYYYY to fast.

S

Edited February 15, 2013 by Steve Murr