Current UKMO run has a triple point on the front over SE England at 0Z
Tues.GFS/NMM has a weak area of CAPE over cent/southern England,warm
advection ahead of the front, a 100kt jet nosing south aloft and rain
turning to snow on a convective band.
Might be interesting as similar features have produced squalls,thunder snow
and weak tornadoes in recent years,

--
regards,
David

add '17' to Waghorne to reply

"Waghorn" wrote in message
...
Current UKMO run has a triple point on the front over SE England at 0Z
Tues.GFS/NMM has a weak area of CAPE over cent/southern England,warm
advection ahead of the front, a 100kt jet nosing south aloft and rain
turning to snow on a convective band.
Might be interesting as similar features have produced squalls,thunder
snow
and weak tornadoes in recent years,

--
regards,
David

add '17' to Waghorne to reply

...and from then on I am sure for once there will be some snow. Impossible
to say exactly where and how much but almost anywhere or even everywhere
could have snow depending on where the lp's, troughs etc decide to go!

Dave
P.S. Looking paticularly good I would think for that snow magnet which is
Dartmoor ;-)

UPDATE Monday1430Z

PPN over Scotland becoming more extensive,further organisation should occur
as front heads south.GFS predicts jet core will be over the west later
today, difficult to say how strong the upper forcing will be on the it's
eastern flank.A smidgeon of CAPE is present in the Herstmonceux sounding at
12Z,and a little low level shear.Likeliest area for thunderstorms is
probably in the southern North Sea where more CAPE is likely to be present
(~100J/Kg at de Bilt, 12Z).
However, I wld think a squall line is still possible over E/SE england
tonight-if a density/gravity current head can form on the nose of cold air
then higher theta air can be mechanically lifted and vertical velocity in a
shallow layer may be high enough for thunder,hail and snow.
Dunno if Will Hand can comment on how well the UKMO mesoscale model handles
such a phenomenon,


--
regards,
David

add '17' to Waghorne to reply

David, yes the mes. usually has a good stab at such features. Looking at the
radar, it may be the SW as opposed to the SE that sees a squall line.

Will.
--

"Waghorn" wrote in message
...
UPDATE Monday1430Z

PPN over Scotland becoming more extensive,further organisation should occur
as front heads south.GFS predicts jet core will be over the west later
today, difficult to say how strong the upper forcing will be on the it's
eastern flank.A smidgeon of CAPE is present in the Herstmonceux sounding at
12Z,and a little low level shear.Likeliest area for thunderstorms is
probably in the southern North Sea where more CAPE is likely to be present
(~100J/Kg at de Bilt, 12Z).
However, I wld think a squall line is still possible over E/SE england
tonight-if a density/gravity current head can form on the nose of cold air
then higher theta air can be mechanically lifted and vertical velocity in a
shallow layer may be high enough for thunder,hail and snow.
Dunno if Will Hand can comment on how well the UKMO mesoscale model handles
such a phenomenon,


--
regards,
David

add '17' to Waghorne to reply

"Will Hand"
David, yes the mes. usually has a good stab at such features. Looking at
the
radar, it may be the SW as opposed to the SE that sees a squall line.

Will.
Well the linear banding in the west evident in radar is now fragmenting
(20Z).The main thrust of cold air is at present over the North Sea.I see the
low centre nr Scandanavia is forecast to drop 10hPa in 12hrs so the PV
forcing must be strong east of the jet.

Now is it worth staying up?

--
regards,
David

add '17' to Waghorne to reply