Model Output Discussion 4th Dec.2013-12z onwards.

[Matty M]

Why does the UKM always get delayed when you are waiting for it!

[Barry12]

Why does the UKM always get delayed when you are waiting for it!

 

It doesn't come out until 5?

[Barry12]

Possible snow event for higher ground on Christmas Eve

 

 

wow

 

Edited December 16, 2013 by Barry95

[Mucka]

GFS wanting to move the PV East again, can only be a good thing in the long term.

 

 

That could be describes as cold zonal I think.

Edited December 16, 2013 by Mucka

[Matty M]

It doesn't come out until 5?

No, it usually comes out at around 4.00-4.15

[Cheshire Freeze]

Just look at this, potential for a real pasting by the wind sometime over the festive season. It's almost as if the vortex has expanded right across the UK

 

 

VERY interesting.

 

Could be a cold deep FI

 

Edited December 16, 2013 by CreweCold

[Barry12]

Just for fun, -8's over Scotland and Northern Ireland at T300

 

Edited December 16, 2013 by Barry95

[Cheshire Freeze]

GFS wanting to move the PV East again, can only be a good thing in the long term.

 

 

That could be describes as cold zonal I think.

 

Low thicknesses despite moderate uppers. Could be some 'wild' weather knocking about....including the potential for heavy snow in places.

[Summer Sun]

Christmas day still looking unsettled

 

 

Snow possible in the north especially on high ground

 

 

After a spell of unsettled weather (as shown above) pressure tries to build

 

 

But another very deep low develops on New years eve north of Scotland once again looks around 940mb if this did come off all new year events in Scotland would be cancelled

 

Edited December 16, 2013 by Summer Sun

[Mucka]

Low thicknesses despite moderate uppers. Could be some 'wild' weather knocking about....including the potential for heavy snow in places.

 

Yeah, if you're going to have no blocking and wild weather then that's about as good as it gets for transient snow events here in the NW. Thunder snow? 

 

Shame it is FI and will be MIA next run. 

[Cheshire Freeze]

Yeah, if you're going to have no blocking and wild weather then that's about as good as it gets for transient snow events here in the NW. Thunder snow? 

 

Shame it is FI and will be MIA next run. 

 

Yes, definitely the best of a bad situation. Thundersnow events would be likely in places if the 12z is anywhere near eventual reality.

 

With such low thicknesses, upper air would be dragged down to the surface quite easily I think. If you look on the Netweather charts (once updated), I suspect thickness values will easily be sub 528 dam across a lot of the UK. Certainly not warm into FI.

Edited December 16, 2013 by CreweCold

[Matty M]

UKM still not making much of Wednesday's system @ 48hrs

 

How can there be such big differences at this range?

 

Edited December 16, 2013 by Matty M

[Summer Sun]

UKM still not making much of Wednesday's system @ 48hrs

 

How can there be such big differences at this range?

 

 

This is GFS to compare

 

 

They look quite close to me, 10mb difference in the depth of the low but the position very similar

Edited December 16, 2013 by Summer Sun

[Cheshire Freeze]

UKM still not making much of Wednesday's system @ 48hrs

 

How can there be such big differences at this range?

 

 

More worryingly (for some), a mix of the UKMO and GFS would produce a well developed low crossing the middle of the country. The deeper the low is, the more it will recurve up the western side of the UK. A less developed low (but potentially still very potent) would track more W-E.

[fergieweather]

UKM still not making much of Wednesday's system @ 48hrs

 

How can there be such big differences at this range?

 

Because as they've been stressing, it's finely balanced & considerable uncertainty remains on depth of development. Some minor mismatches noted today on imagery versus modelling merely emphasise the difficulty.

[Cheshire Freeze]

Ouch...devastation if that occurred (worst case scenario)

 

[That ECM]

Just look at this, potential for a real pasting by the wind sometime over the festive season. It's almost as if the vortex has expanded right across the UK

 

 

VERY interesting.

 

Could be a cold deep FI

 

Hastily sending new letter to Fartamissmuss as my daughter calls him.

Forget the sledge, I'll have a kite!!

Ps I have been good, no warning points!!

Thanks.

Edited December 16, 2013 by No-Time Toulouse

[Mucka]

UKMO and GFS in broad agreement out to 144h

 

[Cloud 10]

JMA cooks up thursday's storm with the North-West,especially Northern Ireland

taking a battering.

 

[Skyraker]

Yes, definitely the best of a bad situation. Thundersnow events would be likely in places if the 12z is anywhere near eventual reality.

 

With such low thicknesses, upper air would be dragged down to the surface quite easily I think. If you look on the Netweather charts (once updated), I suspect thickness values will easily be sub 528 dam across a lot of the UK. Certainly not warm into FI.

 

 

You're right mate.

 

[Matty M]

Yes peturbation 11 would lead to widespread damage over here in Ireland.

 

http://modeles.meteociel.fr/modeles/gens/run/gens-11-1-60.png?12

[Cheshire Freeze]

Yes peturbation 11 would lead to widespread damage over here in Ireland.

 

http://modeles.meteociel.fr/modeles/gens/run/gens-11-1-60.png?12

 

Pretty much as potent as a hurricane that. Gusts over 100mph easily.

[MR EXTREMES]

I agree not mild at all average slightly below here in the south and cold enough for a white Christmas for northern areas if the gfs is correct its also got support from the jma aswell.

 

so theres a good chance of white Christmas in Scotland northern England Ireland and north wales so far so good for our northern friends I really hope it happens for you all. 

 

we might have to wait here in the south but slight signs of depression starting to move a little more se.

 

but be warned this is the gfs were talking about the ukmo don't look that impressive but who knows these features are very very hard for models to get 100% correct even with in the t96 area but looks good for some.

 

the gem is looking very nice indeed.

Edited December 16, 2013 by emotional rollercoaster

[lorenzo]

Ouch...devastation if that occurred (worst case scenario)

 

http://modeles.meteociel.fr/modeles/gens/run/gens-11-1-60.png?12

 

Not far away from the GME/DWD projection.

 

GFS / GEM / UKMO

 

Quite a variety of solutions and looks like this will be all about timing with respect to how deep rapid cyclogenesis takes the system, which in turn looks to be decided by how fierce the jet it is. GFS as one may expect given it's bias for feedback and deepening of lows in the extreme. GEM which we have seen  dartboard happy over the last couple of months sees a slower evolution.

 

With our experience of not trusting output until the UKMO is on board, over to the fax output !

[Man With Beard]

More and more output suggesting the PV might be dragged towards Scandi between Christmas and New Year. Definitely snow potential if that happens as winds will back N after low pressure clears. No signs of extended cold as no significant build of heights afterwards.