Heavy snow has fallen in the Cairngorms, as well as lower areas such as Aviemore. Visitors to Glen Coe and Ben Wyvis will also notice a blanket of snow after temperatures plummeted at the weekend.
Ladbrokes now make it 4/5 that snow falls on Christmas Day, with Aberdeen the favoured city with odds of 7/4, or there is a 5/1 chance of London becoming a winter wonderland.
But hats and scarves will be needed before the festive season after forecasters warned that the mercury was set to plunge to as low as minus 7C (19.4F) in parts of Scotland last night.
Met Office forecaster Marco Petagna said it was too early to tell whether or not a white Christmas was on the cards, but bookies said they have taken a flurry of bets.
Coral's John Hill said: 'We've taken an avalanche of bets on this year being a white Christmas as punters are convinced that everybody's dream will become a reality with snowfall in mainland UK on Christmas Day.
'We've not seen a gamble this early on there being a white Christmas for many years, therefore we'll be keeping our fingers crossed that temperatures don't continue falling over the next six weeks otherwise it won't just be Santa handing out presents this Christmas.'
Jessica Bridge of Ladbrokes said: 'The odds are falling as quick as the mercury, and it looks like the bitter weather is here to stay.'