A blast of Arctic air will bring freezing temperatures to the UK this week and end what has been a mild start to the new year.
Overnight frost and the possibility of rain showers turning snowy in some parts are forecast by the Met Office, though no weather warnings have been issued.
After a mild Monday and Tuesday, temperatures are expected to fall to freezing overnight from Wednesday.
Bonnie Diamond, a meteorologist, said the cold polar air from the north-west will switch to a colder Arctic airflow from the north.
“Through Wednesday a polar maritime air mass is going to push in from the west, but by the time we get to Thursday it will be an Arctic air mass,” she said.