British Airways has cancelled a number of flights from Heathrow this morning, while some airports remain closed while staff work to clear snow from runways.
An amber warning for snow is set to last until 1100 in parts of south-east England, while a yellow warning for ice and snow is in effect for parts of north and east Scotland and areas in England and Wales.
BA says the adverse weather conditions will affect some of its short-haul flights, with multiple service from Heathrow cancelled or delayed. The airline is advising passengers to check the status of their flight before travelling to the airport.
Meanwhile, Bristol airport has suspended flights until at least 1200 while snow is cleared from its runway, though it warns that "the majority" of flights have been cancelled for the remainder of the day.
On trains, Great Western Railway said services could be disrupted until 1300 and Southeastern has introduced an emergency winter timetable for this morning after delays and cancellations yesterday.
Transport for Wales is advising travellers to expect delays to some routes until 1400.
Elsewhere, the Met Office has warned of dangerous driving conditions, with roads in the worst affected areas covered in snow, slush and ice.
Snowy conditions in the south are expected to clear throughout the morning, but the Met Office predicts more snow showers in Scotland and the north-east of England through Friday.