Potential Snow Event - 24th/25th November

[Ben Sainsbury]

Low pressure moving up through the Bay of Biscay Friday into Saturday, northerly winds across much of the UK bringing -5'c 850hpa temperatures could bring the potential for a snow event across much of Central UK during Saturday morning. Timing is key here whether the low moves up through the night or during the day & whether enough cold air can wrap around the low pressure as it exits NE'wards. Low probability of a snow event given it's still 3-4 days away.

Apologies if a thread has already been set up for this & if it is in the right area, not been active in a while. 

 

Edited November 21, 2017 by Ben Sainsbury

[NorthYorksWeather]

Current hotspot as posted by Summer Sun in the MOD looks to be the Yorkshire Dales and Northern Pennines.

We must be wary as ECM currently doesn't agree with the GFS/UKMO scenario.

I would imagine it MAY be resolved by the 12zs, see you there Ben.

[Summer Sun]

35 minutes ago, vizzy2004 said:

Current hotspot as posted by Summer Sun in the MOD looks to be the Yorkshire Dales and Northern Pennines.

We must be wary as ECM currently doesn't agree with the GFS/UKMO scenario.

I would imagine it MAY be resolved by the 12zs, see you there Ben.

 

Yep, could be as much as 5 inches in those areas if GFS is right

[Thermohaline Conveyor]

Wintry PPN signal for Pennines, Scottish Highlands, and higher ground of N Wales toward the end of this week and into the weekend period.  Any signal for snow to lower levels below 400m is inconsistent, with mainly any appreciate snow signal related to an area of rapid cyclogenesis modelled by the GFS.  As a few have alluded to already ECM guidance diverges from the GFS in the rigorous cyclogenesis solution but does maintain a cyclonically dominated regime with wintry signals for NW England, perhaps to lower elevation in places.  12Z ECM and GFS will be interesting viewing.  The probability of snow falling and accumulating is greatest across higher elevation 300-400m (hills and mountains) of England, Scotland and Wales - more especially at the end of this week into the weekend.  Elsewhere, the probability of snow falling to lower elevations is around 30-40% in the North, lower still in the South.  North West England is the exception with some generic signals from the Euro of the 0oC isotherm lowering below 200m in places, supporting a wintry mix of sleet and snow - again though this is one to watch and remains inconsistently modelled.

[weirpig]

Pin the tail on the Donkey at the moment in regards to the Low pressure on Friday Night-Saturday Morning   Gfs OPP has it tracking North  The Gfs Ensembles have it anywhere from John O Groats to Lands End.  The Arperge favours Midlands south. And the Ecm dosent really want to Know.     Either way wherever it does track Elevation will be paramount in situations like this. My opinion (for what its worth)  200m for wet snow  300+ for the real deal.    we shall see.

[toggerob]

It's still 4 days away yet from the main-event but if it happens it'll be quite a substantial covering from what snow-forecast is predicting.

[NorthYorksWeather]

Can't post charts but latest GFS shows a slight southwards adjustment of the front. Snow down to modestly low levels on northern edge.

[NO LONGER POSTING]

These will be interesting to watch over the next few days... In the blue, with some height.. You might be in for a surprise! 

Want them DPs to drop as quick as possible..

Classic rain to snow event, as ever some to far far better than others and the slight detail makes massive difference ... 

Easy tiger... just for fun

[I remember Atlantic 252]

Fantasy 3cms no way

[iand61]

Bound to get plastered in my location, I'm in London for the weekend

[Mokidugway]

Anyone above 3000 metres is in with a chance by the looks of it . 

[iand61]

9 minutes ago, Mokidugway said:

Anyone above 3000 metres is in with a chance by the looks of it . 

Need a weekend job as a Llama herder in the Andes then.

never mind if it's a choice between a bit of wet slush and a weekend on the beer I'll take the beer, even if it's a London variety.

[Thermohaline Conveyor]

On 21/11/2017 at 12:56, Thermohaline Conveyor said:

Wintry PPN signal for Pennines, Scottish Highlands, and higher ground of N Wales toward the end of this week and into the weekend period.  Any signal for snow to lower levels below 400m is inconsistent, with mainly any appreciate snow signal related to an area of rapid cyclogenesis modelled by the GFS.  As a few have alluded to already ECM guidance diverges from the GFS in the rigorous cyclogenesis solution but does maintain a cyclonically dominated regime with wintry signals for NW England, perhaps to lower elevation in places.  12Z ECM and GFS will be interesting viewing.  The probability of snow falling and accumulating is greatest across higher elevation 300-400m (hills and mountains) of England, Scotland and Wales - more especially at the end of this week into the weekend.  Elsewhere, the probability of snow falling to lower elevations is around 30-40% in the North, lower still in the South.  North West England is the exception with some generic signals from the Euro of the 0oC isotherm lowering below 200m in places, supporting a wintry mix of sleet and snow - again though this is one to watch and remains inconsistently modelled.

Original thoughts of some snow or wintry precipitation to lower levels for North West England seem to be supported more now by the GFS.  Not much change in my thoughts.  Although the presence of a strong unstable NW Pm airflow could promote a few surprises mainly in the form of moisture streamers extending from NW England into the N Midlands area.  At the moment though the streamer potential is just a theory based on moisture content, instability and the strength of the upper flow.  A cold weekend for may! Brrrrr