Britain has endured the coldest night of 2012 so far, with temperatures dropping as low as -18C.
The lowest temperature since 2010 was measured in Chesham, Buckinghamshire, during the early hours of Saturday morning - but readings were expected to have dropped even lower elsewhere.
Claire Allen, forecaster for MeteoGroup, said: "Overnight we have had the coldest temperatures this winter so far.
"Most places in England and eastern areas of Wales dropped to below -4C, with -5.8C at Heathrow and -5.5C in Nottingham."
The continuing cold-snap has prompted forecasters and driving groups to warn those travelling over the start of the school half term to be extra vigilant, as many roads are potentially extremely icy.
Drivers are advised to carry hot drinks and extra clothes in case they get stuck.
A "yellow" severe weather warning instructing people to "be aware" of ice on roads has been issued by the national weather service, with much of Britain expecting a dry and clear Saturday which will prolong the freezing weather.
Temperatures are not expected to rise above freezing in much of the UK throughout the weekend, although rain is due to hit the west later.
Sports fixtures have been hit by the weather, with Crystal Palace's Championship clash with Doncaster postponed due to a frozen pitch and a number of games in League One and League Two axed.
The race meetings at Newbury, Uttoxeter and Warwick have also fallen victim to the cold.