It’s kinda an all or nothing upcoming 5-7 day period for us. This ‘cold spell’ will be nothing special if we don’t get much in the way of snow on the ground except the higher elevations but with a widespread snow cover and with a 1032 surface high covering the UK, there’s the potential for the coldest nights since Dec 2010.

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You don’t get a much better upper 500mb height anomaly pattern than this.

Without a decent snow cover by Saturday and by that I mean snow cover through the Central Lowlands and a decent swathe of England and Wales, arctic air masses are essentially wasted.

The ECMWF still suggests a decent snow cover developing over the next 96 hours.

GFS snow cover as of 06z Sat morning.

These are the ECMWF overnight minimums based on the above snow cover projected.

These numbers will be about right if there’s less snow coverage but would likely be underdone if the model is correct with it’s snow cover at 96 hours.

Amount of snow cover and how cold it gets by night will determine how cold the days are Sat-Sun.

It’s currently chilly but nothing arctic as of yet. Low pressure spinning over the UK and simply cycling cold air around but once the circulation slides east and heights build west of Ireland, in comes the arctic air.

The blustery showers containing rain, sleet and snow of today are now beginning to ease and a small high builds in, this sets the stage for a colder night to come from Manchester to Inverness.

Then another weak system moves in tomorrow and with slightly cooler air, this may support snow to lower levels tomorrow evening.

That system then exits during Friday and once this leaves the stronger push of arctic air dives down over the UK at the same time a more significant surface high builds in late week into the weekend.

We’re also continuing to closely monitor a low crossing the Bay of Biscay and eventually northern France during Friday. Moisture wrapping around the low into colder air over England may present a covering of 1-2 inches around London and East Anglia.

Here’s the ECMWF showing the next 3 day scenario.

Models are in pretty good agreement that the day 5-10 day sees the return of milder Atlantic air once again.

EPS Control

GFS ensemble

See today’s video for the discussion.

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