Winter Model Discussion 12Z 15/1/13 onwards.

[chionomaniac]

A look at what the rest of the week is likely to bring - including the possible battleground scenario...

Cold Spell Latest - What Happens Next

Excellent summing up.

Who is MH?

[swfc]

Taken from IF in the Sw and C S england regional thread..

"NB Latest NAE progression across to meridian with PPN Thursday rejected for now and operational version heavily modified - in case anyone looks at raw stuff and starts hyperventilating. However.... Chief awaiting next UKMO-GM to be sure, so we await confirmation on expected evolution. Atlantic push of milder air much faster on new NAE through Thursday, hence much to play for in terms of broader evolution thereafter IF the NAE prog has any validity. At the moment... we lean otherwise."

sorry could you translate that please .thanks

[Cheshire Freeze]

Taken from IF in the Sw and C S england regional thread..

"NB Latest NAE progression across to meridian with PPN Thursday rejected for now and operational version heavily modified - in case anyone looks at raw stuff and starts hyperventilating. However.... Chief awaiting next UKMO-GM to be sure, so we await confirmation on expected evolution. Atlantic push of milder air much faster on new NAE through Thursday, hence much to play for in terms of broader evolution thereafter IF the NAE prog has any validity. At the moment... we lean otherwise."

Yes, my first thought was 'it's gone off on one'

[Man With Beard]

The NAE is a big surprise - Thursday now another snow event for central/western areas - rain into the SW. Has this just come out of nowhere or have a missed something?

However, the pressure pattern for Europe hasn't changed too much - a little further east but not much:

NAE:

UKMO:

And still looking good for undercut on Friday/Saturday

Edit: just seen note from IF above - well, we shall see!

Edited January 15, 2013 by rjbw

[WhiteFox]

Yes, my first thought was 'it's gone off on one'

I think it means: they don't buy the NAE solution and are waiting to see what the other models come up with for the 12z runs...

[Matty M]

GFS 12z good.

Rain turning to sleet and snow as cold fights back Friday.

[-uksnow-]

sorry could you translate that please .thanks

Basically the NAE that is showing a poor breakdown and much warmer uppers in by thursday has been rejected by the MO is how i interpret it, but they are waiting for further confirmation from the 'Chief' to double confirm this.

Yes, my first thought was 'it's gone off on one'

Lets hope so eh..

[Matty M]

Run to run inconsistencies at early timeframes are amazing at the moment.

[bluearmy]

ukmo is 50 -70 miles east as per matty m comments. sort of ties in with NAE more progressive nature

[TEITS]

Typically expected swing back W on the 12Z compared to the 06Z.

Good snowfall totals from this because the front is so slow moving.

[-uksnow-]

UKMO at 72 - Better than the GFS but even the GFS is GOOOOD.Nice und

ercut on that UKMO.

[Rob K]

On GFS the -5C isotherm is actually heading WEST from Wales northwards as the front pivots! Lovely.

[No Balls Like Snow Balls]

UUUUMMMMM - 12hours + of snow for most of country if GFS comes off

[Methuselah]

ukmo is 50 -70 miles east as per matty m comments. sort of ties in with NAE more progressive nature

70 miles further east and good potential for a slider?

[Summer Sun]

The met office probability maps have updated

[Liam J]

WOW look how cold the 850 temps that are managed be to pulled back west and undercut the front! Nice

http://www.meteociel...h=72&carte=1007

Edited January 15, 2013 by Liam J

[Matty M]

Now we need the UKM GM to hold steady after a very good GFS 12z.

[Wayneywoo]

Again, 12z giving better (more consistent with other models) output than the 6z. It's as if the 6z gives us worst case scenario and the 12z gives us most likely scenario then 18z mostly best case scenario.

Having said that, I wonder if the programming of the three outputs is skewed in any way to reflect that....

[Harsh Climate]

If runs stay like this overnight, what chance of fridays warning being spread further north east tommorow?? Highly likely IMO

Edited January 15, 2013 by Harsh Climate

[bradymk]

undercut forces cold uppers back west, better 12z run, and happy with this as still hoping for a sig snow event here Friday (Extremely rare)

[The Northern Ramper]

Short term the Gfs is awesome and we are talking just t72 onwards here.

[Summer Sun]

Away from the far south west there are some widespread high snow totals by Saturday morning

Won't be many sporting events on this weekend if that comes off!

[Matty M]

UKM solid enough at T72hrs.

Although it does take the cold a bit further east in earlier hours but not as much as the NAE

[Harsh Climate]

I will bank this run, gives west yorkshire a 24 hour fall of snow

[The Northern Ramper]

If runs stay like this overnight, what chance of fridays warning being spread further north east tommorow?? Highly likely IMO

If the Gfs is how things turn out then that warning will be most of the uk and upgraded.