UK Weather
And plenty of last-minute shoppers have been caught out.
It's only the second time in living memory.
Parts of Britain are a full 10C warmer than usual today.
Look out for vulnerable neighbours, agency says.
It wasn't always a giant sand pit.
One Welsh village had the coldest November night for six years.
Odds of 2/1 for a white Christmas in some cities.
Video and pictures from the scene showed the street under water.