Bookmakers are set to see the number of bets on a white Christmas increase this week as thermometers plunge around the country.
October temperatures have been reasonably mild until this week, but the arrival of Arctic air is now expected to cause freezing conditions and snow showers in some parts of the UK.
Sky News weather forecaster Sarah Pennock said the next few days will mark "the beginning of a rapid slide into quite wintry conditions".
Meanwhile, William Hill spokesperson Rupert Adams revealed that the bookmaker has already seen increased activity in its white Christmas betting market this week.
"We expect to be very busy in the next few days with the first heavy snowfalls expected," he said.
William Hill is currently offering 6/1 on Christmas Day snow in Glasgow, with a white London priced at 8/1.
Long-range weather forecasts indicate that this winter will be milder than average but colder than last year.
Bookmakers are set to see the number of bets on a white Christmas increase this week as thermometers plunge around the country.