Model Output Discussion 13/11/13 >

[Panayiotis]

GFS is actually exhibiting a significant shift towards ECM this evening RE LP in the Atlantic. Doesn't look to be nudging NE into the block as significantly as the 12z had it.

 

Steve Murr beat me to it!

And me! 

[Geordiesnow]

I hope the Gem 12z will be the way forward with the high eventually migrating into scandi and a strengthening very cold and roar ene'ly flow and then an atlantic low undercutting the cold block and bringing blizzards and gale force easterlies.

 

What the?? Come on Karl you should know better than mis lead people like that. That chart does not show any blizzards at all and you should know that. I think because of the warm SST's we may get away with a brighter set up with some showers but certainly no blizzards and very limited snowfall with any being reserved to the higher ground due to the high SST's and lack of significant cold air. 

 

The set up from the GEM can't be ruled out as the GFS op runs have hinted at that previously but the high very slowly but surely landing on top of the UK does look the most likely outcome at this stage which should lead to some wintry weather in terms of night time frosts aslong there is not much cloud getting trapped within the high.  Can easily change though and hopefully we see more output like the ECM and have winds coming from the North. 

[karlos1983]

I hope the Gem 12z will be the way forward with the high eventually migrating into scandi and a strengthening very cold and roar ene'ly flow and then an atlantic low undercutting the cold block and bringing blizzards and gale force easterlies.

 

Would need to be colder though surely,!

[Mark Neal.]

GFS certainly extends the snow-line and makes less of the warm sector. Meaning Northern England seeing more wintryness.... Snow over higher ground?

 

6AM Wednesday..- Rain turning to snow in Scotland...

 

12pm- Wednesday. Snow showing for Northern England..

 

6pm- Wednesday. Snow Showers following on behind across N Wales & W Scotland and along NE Coast (further inland). Back Edge snow further south as colder air digs in behind..

 

Obviously its the first run where it has showed much more in the way of a wintry mix, so quite possibly an outlier, Met Office see it as a rain event with the warm sector well to the East, something to watch anyway as we get closer... Could be some snowflakes from this, even as far south as Midlands perhaps?

Edited November 17, 2013 by Mark N

[bluearmy]

At day 6 gfs 18z sends most energy into the southern arm off the eastern seaboard. Wonder how long it can maintain that.

[andymusic]

a nice snowy map for ya's all

 

 

 

then Wales looks in the firing line after that

 

 

 

[Panayiotis]

Its a positive sign seeing the low in the Atlantic move south on this run and its something which we need to look for in future runs:

However as you can see, not enough heights on this run are moved northwards which allows the low to move up and over the high.

Edited November 17, 2013 by Panayiotis

[radiohead]

It seems how Invest 98L (the low in the Atlantic) merges (or doesn't) with another low coming off Newfoundland around T96 that could make a big difference with regard to what happens down the line.

 

Intensity and track not nailed down at all. Some models keep it as a weak TS, others take it to hurricane status.

 

 

Edited November 17, 2013 by radiohead

[cheese]

a nice snowy map for ya's all

 

 

 

then Wales looks in the firing line after that

 

 

 

Those European-wide precipitation charts are quite misleading. Here is what it shows in more detail:

 

 

[Geordiesnow]

The 18Z had the low slightly further Eastwards in the North Sea hence the air is a tad colder on the western flank but too me, I still don't see much snowfall on Wednesday, perhaps some backward edge snowfall as the cold air undercuts the PPN? Probably only be reserved to higher elevations I would of thought. 

 

The main risk for snowfall looks like Monday night into Tuesday morning across Northern and Western areas, even down to lower levels perhaps. Also a brief window for NE Scotland to see some wintryness in any convective showers. Main message is to enjoy any snow you see because it will be quite brief! 

 

18Z does not look like the ECM too me, no retrogression into Greenland, everything much further East and the high very close by resulting in a dull damp cloudy NE'ly flow.

[SMU]

Big huge blocked FI coming from the 18z- but its all wrong anyway.- but good to look at-

 

http://modeles.meteociel.fr/modeles/gfs/runs/2013111718/gfsnh-0-162.png?18

 

S

[Frosty.]

I'm not misleading anyone, the Gem shows potential with the high migrating into scandinavia and strong cold enely winds flooding across the uk, an atlantic low could undercut the block and the result would be mucho snow. I'm sure I'm not alone in seeing the potential. :-)

[Snowman.]

It seems how Invest 98L (the low in the Atlantic) merges (or doesn't) with another low coming off Newfoundland around T96 that could make a big difference with regard to what happens down the line.

 

Intensity and track not nailed down at all. Some models keep it as a weak TS, others take it to hurricane status.

 

 

Sooo some models want a Hurricane developing in the Atlantic?

 

Rigghhhhhhhhhhttttttt.

[Snowy L]

GFS eventually seeing the split close to t+180, I'm guessing we'll get a block on this but it's pointless speculating. It's still got the t+96-t+144 period wrong imo.

[radiohead]

Sooo some models want a Hurricane developing in the Atlantic?

 

Rigghhhhhhhhhhttttttt.

 

NHC forecast :

 

ENVIRONMENTAL CONDITIONS APPEAR CONDUCIVE FOR THIS LOW TO ACQUIRE SUBTROPICAL ORTROPICAL CHARACTERISTICS DURING THE NEXT FEW DAYS WHILE IT MOVESSLOWLY NORTHWARD TO NORTHWESTWARD. THIS SYSTEM HAS A MEDIUMCHANCE...40 PERCENT...OF BECOMING A SUBTROPICAL OR TROPICAL CYCLONEDURING THE NEXT 48 HOURS...AND A HIGH CHANCE...70 PERCENT...OFBECOMING A SUBTROPICAL OR TROPICAL CYCLONE DURING THE NEXT 5 DAYS.

[Cheshire Freeze]

Oh aye, what's happening here then? Certainly more interesting than the 12z so far

 

Edited November 17, 2013 by CreweCold

[Snowman.]

 

 

That low approaching the SW is keeping the high up and moving up which should help the trough off greenland descend upon us.

[I remember Atlantic 252]

hope 18Z is wrong, it shows a miserable damp weekend for England and Wales

[Captain Shortwave]

18Z does not look like the ECM too me, no retrogression into Greenland, everything much further East and the high very close by resulting in a dull damp cloudy NE'ly flow.

Really?

I cursed it again didn't I 

Edited November 17, 2013 by Captain shortwave

[Snowman.]

NHC forecast :

Brilliant.

 

Got to love it ey, where now relying upon a tropical cyclone.

Up, up and awayyyy

 

[Cheshire Freeze]

GFS starting to smell the coffee? In your own time Mr Global Forecasting System...

[Snowy L]

Just look at that vortex reform so quickly in early FI. oh GFS... you don't help yourself do you?

[liam300]

The 18z puts high pressure over the UK at 228h FI

[SMU]

http://modeles.meteociel.fr/modeles/navgem/runs/2013111718/navgemnh-0-108.png?17-23

 

18z NAVGEM pretty much inline with the ECM-

 

Looks like the GFS is going to get PWNT again but every model out there.

[johnholmes]

I hope the Gem 12z will be the way forward with the high eventually migrating into scandi and a strengthening very cold and roar ene'ly flow and then an atlantic low undercutting the cold block and bringing blizzards and gale force easterlies.

 

I think you are losing the plot with all your enthusiasm old lad. Blizzards=please explain to us all how?