A cold snap is on the way after a weekend of mild temperatures across the UK.
Forecasters have warned that temperatures will plunge toward the end of January, despite above-average figures over the last few days.
The Met Office cannot say whether the UK will be hit with snow, and rumours of a Beast from the East sequel are not confirmed.
Saturday and Sunday will remain mild, with temperatures hovering at about 8C or 9C (46F or 48F) – above average for this time of year.
But in a couple of weeks’ time, the temperatures will fall to about 3.5C (38F), below the January average.
Sky weather producer Joanna Robinson said: “The rest of the weekend looks mild, with temperatures widely reaching 9C to 11C (48F to 52F) again on Sunday after a frost-free start.
“Colder air will move into northern Scotland later, with showers there turning increasingly wintry.
“Sunday night will bring a widespread frost to the north of the UK, with icy stretches possible.
“Monday looks relatively colder, but Tuesday and Wednesday will see a recovery in temperatures again.
“Thereafter, it looks to become colder across the UK due to the recent stratospheric warming event, but brief milder interludes can’t be ruled out.
“The likeliness of a significant cold spell becoming established towards the end of the month is increasing, but how long that will last and how much snow it may bring is still uncertain.”
A Met Office spokesman said: “Next week there will be colder spells and there could be a little bit of winteriness in the north, but nothing too exceptional for this time of year.
“As we head towards the later part of January it will turn colder, but there’s still a lot of uncertainty in that forecast about where any snow will fall.
“The week beginning Monday 21 January, there is a stronger signal of it getting colder, that would increase the risk of snow across the UK.”
Forecasters have said the same weather pattern – which sparked last year’s Beast from the East, bringing freezing temperatures and heavy snow – could return.
A sudden stratospheric warming appeared around Christmas, when there was a sharp increase in temperature over a couple of days.
When this happens in the Arctic, it can lead to a rush of cold air blowing eastwards across Europe a few weeks later. This brings much cooler temperatures across the continent.
Temperature maps from the European Commission indicate Britain will have temperatures of about 2C to 3C during the second half of January, slightly cooler than average for this time of year.
Although the Met Office is not ruling out a Beast from the East, forecasters believe the weather will be stable.
A spokesman added: “There is nothing in the next week or so that could indicate any change like the Beast from the East.”