I’ve just been having a look through the history weather archives and it seems the last time the Polar Vortex made its way South into the United Kingdom was 1955 so what we’re about to see over the next couple of days really is a very rare event indeed and some areas could see some very severe weather, so it’s advised that you keep upto date with the latest forecasts and warnings, I’ll be issuing a severe weather warning later this evening for Saturday.
Before then though, what can we expect? Through Thursday morning and into the early afternoon a very active Cold Front will be running Southwards across the United Kingdom, this will bring a spell of moderate rainfall, locally heavy across many parts of the country, however as that cold front digs Southwards much colder air will flood South with it, so don’t be too surprised to see a short period of snowfall following on behind, though accumulations are unlikely.
The first significant spell of snowfall will come on Friday when winds back to a strong North-West direction, this will blow biting cold winds over the relatively warm Irish Sea sparking that convection and developing those snow showers. The areas that look most at risk from this will be the Northern and Western Coastal areas of Scotland, North-West England, Northern Ireland, North-Western Wales and South-West England. We could also see something called the Cheshire Gap Streamer developing and this has the potential to drive showers South-Eastwards across the Midlands and down towards Central Southern England and South-East England, though these showers typically become lighter and more scattered the further inland they head. Accumulations in some spots could hit 10-15cm, but widely 1-5cm is more typical. Further East a beautiful day with lots of sunshine.
Saturday is when things become tricky and possibly severe, a low moving area of low pressure sitting somewhere over East Anglia/South-East will bring a spell of very heavy snowfall to The Midlands, South-West England, Wales, Central Southern England, South-East England and East Anglia before heading Northwards to affect more North-Eastern parts on Sunday. There is still a lot of uncertainty to the tracking of this low pressure system for Saturday and Sunday so the areas at risk could change, though a large part of the country looks set to see at least some snow.
Northern England and much of Scotland look likely to miss out on the worst of the snowfall with showers generally confined to coastal areas here, but because of this some very low temperatures are likely to be recorded in the coming days.
Although some models are showing a potential less cold scenario coming in Tuesday/Wednesday, there is also good support for colder weather to continue up and into the Christmas period. For this reason, Northern areas stand the highest chance of seeing snowfall on Christmas day, whilst further South the risk is lowered due to that potential for less cold weather. Heres the percentage risk for how things currently stand.
North – 75%
South – 50%
East – 65%
West – 45%