Fresh yellow weather warnings for ice have been issued for many areas of the UK, as some areas are threatened with blizzard conditions on Thursday.
An amber warning for snow - covering northeast England, including Scarborough, Whitby and parts south of Middlesbrough - is in force until 9pm on Thursday.
UK weather latest: Blizzard warning for amber area
The Met Office said there could be "significant snow accumulations" over the North York Moors and parts of the Yorkshire Wolds with up to 25cm (10ins) on hills above 100m (330ft).
"Gusty winds, giving occasional blizzard conditions, and perhaps a few lightning strikes, may accompany some of the showers, posing as additional hazards," the warning added.
Some A-roads in North Yorkshire were reported to be "gridlocked", according to Shingi Mararike, Sky News' North of England correspondent, but he added gritters are out to deal with the bad weather.
Snow ploughs have been hard at work on the North York Moors and a thick coat of snow is covering the A169 between Pickering and Whitby.
Dozens of schools have been closed in North Yorkshire and Scotland.
A number of yellow warnings are also in force for snow and/or ice across large parts of Britain.
In many of the warnings issued by the Met Office, there are concerns that where "showers persist and/or snow partially thaws and then refreezes overnight, this will bring a risk of ice".
Jo Wheeler, Sky's weather presenter, said clear skies will allow temperatures to tumble again as Thursday night approaches, "with an early and severe frost expected, and the associated risk of icy stretches on untreated roads and pavements".
Coldest night so far
Overnight Wednesday into Thursday was the coldest of the season so far, according to the Met Office.
Temperatures dropped as low as -6.6C (20F) in Benson, Oxfordshire. There were two -6.4C (20F) temperatures recorded in Wales (in Sennybrigde) and in Scotland (Dundreggan).
While in Northern Ireland it fell to -2.8C (27F) in Altnahinch Filters.
Cold health alerts in force
As well as the one amber weather warning covering parts of the UK, there are two amber health alerts in place in three areas of England from the UK's Health Security Agency.
An amber health alert is designed to prepare health services, including for the potential for a rise in deaths among the over-65s and people with health conditions.
The alerts are in effect in North East and North West England, along with the Yorkshire and the Humber region until 8am on 22 November.
Yellow cold-health alerts are in place for the rest of England and also expire at the same point.
Walk like a penguin
NHS Greater Glasgow and Clyde (NHSGGC) is recommending that people should walk like penguins to avoid dangerous slips and trips on icy surfaces.
The technique, which went viral in previous winters, is back for 2025 as part of the health board's winter campaign.
Laura Halcrow, falls prevention lead at NHSGGC, said: "It might look funny, but waddling really works. A slip on ice can cause painful injuries and even hospital stays, especially for older people."
Turning wet and windy
Sky's weather presenter, Jo Wheeler, adds that the forecast is set to change this weekend.
"We'll trade the cold sunshine and wintry showers for wet and windy conditions with rain turning heavy as it crosses the country on Saturday."
"The British weather, fickle as always, looks like delivering a brief change to this milder westerly flow followed by an equally quick change back to a chilly northerly flow."
(c) Sky News 2025: Fresh weather warnings issued as parts of UK threatened with blizzard conditions
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