Freezing conditions and heavy snowfall brought chaos to Britain's transport network on Tuesday, shutting airports and disrupting train services.
The Met Office said temperatures fell to as low as minus 10 C overnight with as much as 25 cm of snow predicted to fall in some areas as the weather front spreads south.
There were severe warnings of heavy snow and widespread icy roads across Scotland, northern, central and western England, while more heavy snowfall was expected further south and in London later on Tuesday and on Wednesday.
Manchester Airport was closed until 12 pm because of heavy snow and flights were being cancelled at Leeds Bradford Airport.
Many train services across Britain suffered cancellations and delays with severely reduced services on the East Coast mainline from Scotland and northern England to London because of the poor weather.
Motorists were advised to take care if they had to travel, and the Highways Agency said "continuous salt treatment" was being carried out at high-risk areas.
The AA said it expected Monday to have been its busiest day ever for breakdowns with 25,000 call-outs.
High demand for gas prompted Britain's network operator National Grid on Monday to warn consumption may have to be cut, which encouraged producers to increase flows into Britain.
The Met Office has said it expected the freezing conditions to continue into late January after one of the chilliest Decembers on record.