The Met Office has issued new yellow weather warnings for snow and ice in most of England, Wales, Scotland and Northern Ireland.
Warnings now apply for Thursday and Friday.
Existing warnings now include the risk of snow and ice and have been extended south to cover all of England with the exception of London, the south east and the south coast.
All of Wales is covered, as is the eastern half of Scotland and all of Northern Ireland.
The warning, which comes into effect at 5pm today and will last all Friday, reads: “Showers, a mixture of rainy snow and snow, are expected to fall on frozen surfaces and form icy patches.
“In addition, persistent rain and hill snow is likely to move south across northern England and North Wales on Thursday evening and night.
“This then gradually moves into parts of central and south-west England and south-east Wales on Friday.
“While ice is likely to be the most common hazard, snow is also likely in places.
“Snow is most likely to fall over the Pennines, North York Moors, and the Wales and South West England plateaus, with a possible 2-5 cm.
“Snowfall is possible in other locations, but the accumulation is likely to be small and temporary. Freezing fog is likely to persist and create an additional hazard if visibility is temporarily less than 100 meters.”