This blog is going to be slightly different to the usual ones, I’m going to split it into two separate parts. The first half will be focusing on the snowfall risk through Sunday and the second half focusing on Mondays snow potential.
Through tonight though, any rain, sleet and snow still lingering across Southern parts will clear Southwards, we could have a few problems with ice here as temperatures fall widely below freezing allowing a widespread frost to develop with patches of mist and fog.
Into Sunday and we’re going to start to see the first band of rain, sleet and snow moving into Scotland through the morning. The heaviest of the snow falling across the Scottish Highlands where we could see totals in the region of 10-15cm, though down to lower levels totals closer to 5-10cm. Through the day this band of rain sleet and snow will gradually move South-Eastwards into Northern England, North West England and reaching Northern Wales by the evening.
The chart shows which areas can expect to see snowfall on Sunday. The chart is valid up until midnight and these are the accumulations expected at this point. Whilst yellow areas are likely to see snow falling, accumulations are currently not projected to be much higher than 2-5cm. The purple zone is to cover higher ground where significant accumulations are expected.
Moving onto Monday and we continue to see this area of now mostly snow pushing South-Eastwards, at the same time we begin to see some slightly milder air getting into the mix, this is when things become very uncertain with different models forecasting different things so I will be issuing an update on Mondays snow risk during Sunday afternoon to cover the latest forecast data.
Current models suggest milder air will begin turning snow to rain across Wales and the South-West of England with the snow line hovering somewhere around the Western Midlands, we’ve also got another finger of slightly warmer air coming up into the South-East which raises the Wet Bulb Freezing Level (WBFL) to around 500m, this could suggest that precipitation will initially fall as rain below 500m, particularly along the East before turning to snow as colder air digs back down, as I stress above though there is a lot of uncertainty over this at the moment.
The map above is the total accumulations currently expected by around 6PM on Monday. I haven’t included Scotland or Northern England because that was covered in Sundays snow risk map, this is simply a profession on from then as the front sinks South-Eastwards.
I have placed the far South under the yellow zone for the time being due to the uncertainty over this warm sector pushing up as the front pushes down, we should have a clearer picture by tomorrow (Sunday) afternoon so you might find these values are upgraded or downgraded, this is not the final forecast.
Looking ahead beyond Monday quickly and it looks like it’s going to remain cold with a further snow shower risk on Tuesday and Wednesday across Eastern parts in particular. Towards the end of the week it looks like high pressure will build across the UK keeping things on the cold side, what happens as we move into the weekend is outside of the current possible forecasting time frame.