Possible Winter Storm December 27th

[knocker]

Or to be more precise.

 

 

There is an 80% probability of severe cold weather/icy conditions/heavy snow between 1500 on Friday and 0000 on Wednesday in parts of England. This weather could increase the health risks to vulnerable patients and disrupt the delivery of services. Please refer to the national Cold Weather Plan and your Trust's emergency plan for appropriate preventive action.

 

A spell of wet and windy weather is expected to develop over the UK on Boxing Day and at first on Saturday 27 December. Snow is likely in some northern and central areas, more especially on hills, with some significant accumulations possible. There is also an increasing signal for snow to affect some southern areas. The areas currently at greatest risk are parts of the Midlands, and southern parts of northern England. More settled conditions are expected thereafter, although it is likely to remain cold with widespread night frosts, and with mean temperatures widely 2C or less.

 

An update will be issued when the alert level changes in any region. Alerts are issued once a day by 0900 if required and are not subject to amendment in between standard issue times. Note that the details of the forecast weather are valid at the time of issue but may change over the period that an alert remains in force. These details will not be updated here unless the alert level also changes, the latest forecast details can be obtained at the following link: http://www.metoffice.gov.uk/public/weather/forecast/#?tab=map

 

http://www.metoffice.gov.uk/public/weather/cold-weather-alert/#?tab=coldWeatherAlert

[Darren Bown]

The weather warning shows how unsure they are with this set up, a broad area for a warning, plus uncertainty of rain/snow areas and amounts. I think we will have a rain to snow event with very little lying except the hills, basing on previous similar events.

[knocker]

Forecasting whether it's going to rain or snow and in what specific areas can be very tricky even at these ranges.

[knocker]

Without question I would stick to the METO guidance on this but out of interest the GFS (P)

Chart courtesy weatherbell

 

 

Edited December 25, 2014 by knocker

[Hirudine]

I have to admit, this possibility of snow in the South caught me by surprise! I was just expecting another wet and windy spell.

[knocker]

At this moment I would think the possibility of snow in the south unlikely but as previously mentioned this depends on so many variables it will be a matter of watching tomorrow.

[johnholmes]

This link will show you how complex forecasting snow rather than rain is-hugely complicated. That is even IF the forecast gets where the precipitation is falling in the correct place at the correct time and the correct intensity. Use the link I give to try it out but NOT more than 12 hours before the expected time for decent accuracy.

https://forum.netweather.tv/topic/27989-how-to-try-and-forecast-snow/

 

below is the Fax link showing its latest definite position

http://www.weathercharts.org/ukmomslp.htm

use the link below to follow its path between the Fax positions, not always accurate but the movement gives a good idea on its track and depth.

http://meteocentre.com/analyses/map.php?date=0〈=en&area=eur&size=standard

[Liam J]

Slight correction northwards on the 18z. 

 

18z 12z

Edited December 25, 2014 by Liam J

[Darren Bown]

Definitely a 'wait and see' scenario. The media have the warnings now, so wait for the 'where was the snow' questions Saturday evening if it doesn't materialise!

[knocker]

This evening's JOMOC

http://www.cincfleetwoc.com/HF-Fax/North_Atlantic/matrix.html#matrixLatestZData

 

[Ross Andrew Hemphill]

I'm waiting till tomorrow itself to see what happens because its changed significantly so its really a waiting game. Lets hope for a Northerly correction!!

[Joe Levy]

I'm waiting till tomorrow itself to see what happens because its changed significantly so its really a waiting game. Lets hope for a Northerly correction!!

Some of us southerners who haven't seen any snow since March 2013 are hoping for a southerly correction but to whoever gets snow, congratulations in advance  

[vladthemert]

Looking at Mapanz post winds there convergence in Lincolnshire.  What could happen increase Winds ?, Squall line ?.

Edited December 25, 2014 by vladthemert

[knocker]

Northwood at 0z and METO + 24hrs

 

The latest from the METO has the snow belt Wales, Midlands and east central, mainly on high ground but lower ground in places, Up to 4"" on high ground. Could be quite wet south of this and windy SW and south.

Edited December 26, 2014 by knocker

[Darren Bown]

As knocker has said, another southerly correction. Looks like Wales and Midlands could be in for a treat!

[knocker]

Chief forecaster 0824Z

A depression will track southeastwards across England and Wales during Boxing Day, clearingsoutheast England overnight.A spell of snow is likely, even to lower levels, on the northernflank of this depression. South of the depression centre,rain will fall, heavy at times.There is more confidence now in the track of the depression, the main uncertainty revolvingaround the balance between rain and snow, which depends on the intensity.  Where snow doesoccur accumulations of 2 to 4 cm are likely even to lower levels, with more than 10 cm onhigh ground. There is the risk of 10-15 cm, even at low levels, parts of Wales and the Midlands being most at risk. 

Edited December 26, 2014 by knocker

[stratty]

 

Chief forecaster 0824Z

A depression will track southeastwards across England and Wales during Boxing Day, clearingsoutheast England overnight.A spell of snow is likely, even to lower levels, on the northernflank of this depression. South of the depression centre,rain will fall, heavy at times.There is more confidence now in the track of the depression, the main uncertainty revolvingaround the balance between rain and snow, which depends on the intensity.  Where snow doesoccur accumulations of 2 to 4 cm are likely even to lower levels, with more than 10 cm onhigh ground. There is the risk of 10-15 cm, even at low levels, parts of Wales and the Midlands being most at risk. 

...........still doesn't say where the northern flank will be though!?

[johnholmes]

see the other two threads with information

[Nick F]

As I posted in MOD - a fairly widespread risk of seeing some snow over the next few days across the UK, some may get a covering - especially higher ground, some quite a good covering across parts of Wales, The Midlands, southern half of northern England in the next 12-24 hrs as we see a low scoot SE across Wales and southern England later today, bumping into cold air in place and also sucking in colder air with lower thicknesses and dew points behind it to bring snow to lower levels across England and Wales this evening/tonight - I have done a snow risk map below based on UKMet, NMM4 and GFS snow predictions.

 

 

Snow showers for Scotland and NW England too later today and through Saturday before easing in the evening

 

Once the low clears, risk of some wintry showers for eastern England tomorrow, turning increasingly to snow I should think, by Saturday night, these sleet and snow showers perhaps keeping going across Kent and Sussex on Sunday morning before easing.

 

 

Otherwise, Sunday's looking fairly dry and thereafter right up to New Years Day.

Edited December 26, 2014 by Nick F

[Supacell]

Living in Derby I am in the area likely to see some snow later on today and into the night. Personally I do not think Derby itself will see much if any snow settling but areas just outside here could get a decent snowfall tonight, the best since March 2013, and the Peak District could do especially well. So little snow IMBY but plenty just a short drive away

 

Overall I think anywhere across north and mid Wales, the Midlands, southern parts of N England and East Anglia are in with a chance of seeing snow and with this comes the risk of ice and travel disruption. It is marginal, which makes me think height will be a factor, but not much height will be needed to see a blanket of the white stuff to greet some tomorrow.

[Lauren]

I remember the 2010 winter snow, we were only forercast a small smattering and then we all know what happened then. I'd like to hope that would happen again, but I'm not optimistic.

[Nick L]

To keep all snow-related posts in one place regarding today's fun and games, I'm going to close this thread and keep this one open:

 

https://forum.netweather.tv/topic/82113-boxing-day-snow-event-thoughts-and-reports/