Heavy snowfall has caused major travel disruption across the UK and Ireland, leading to road closures as well as flights and trains being cancelled.
Up to 10cm of snow fell in many areas overnight as Britain's Met Office warned that "snow showers or longer periods of snow are expected on Tuesday, accompanied by very low temperatures."
Many British roads were partially or completely closed, and rail services were cancelled or severely delayed.
The Met Office issued yellow and amber weather warnings for northern and north-eastern areas, adding that snow could cut off some isolated communities and disrupt power supplies.
Dozens of stranded motorists had to be pulled from snow drifts on Tuesday morning, the Automobile Association said.
Vince Crane of the AA said: "With the sub-zero temperatures this week, drivers should allow extra time to properly de-ice the car and check their route before setting off - try to favour gritted roads if possible.
"Accidents happen when people rush so when on the road, leave plenty of space behind the car in front and drive to the conditions."
Frank Saunders, chief forecaster at the Met Office, warned some areas were "likely to see their coldest spell of weather since at least 2013 - perhaps 1991."
Many flights were cancelled to and from Manchester and other northern airports early on Tuesday, but London's two main airports, Heathrow and Gatwick, said they were operating as normal.
Similar conditions affected transport in much of Ireland, where national forecaster Met Eireann said daytime temperatures were as low as -5C on Tuesday and expected to fall further on Wednesday.
Australian Associated Press