Forecasters have warned that people travelling could face difficult driving conditions and transport disruption with snow and ice alerts issued for parts of the country.
The Met Office has issued a yellow snow and ice warning for the Highlands, Western Isles, Orkney and parts of Argyll and Bute and central Scotland which runs from 3pm on Tuesday until midday on Wednesday.
A separate yellow warning of snow in Shetland is in force until 3pm on Tuesday.
Further south, a band of heavy snow could cause disruption later in the week, with as much as 20cm possible in higher areas.
Temperatures will drop as the week goes on, with a yellow snow warning issued which covers parts of Wales as well as northern and central England, the Met Office said.
The warning has been updated and runs from 6am on Thursday to 6am on Friday, while the warning zone has moved north.
It stretches from Cumbria and the Scottish Borders down to Nottingham in England – though it does not reach to the coast in the east – and also covers Northern Ireland and northern Wales.
There is a risk of power cuts, travel delays and some rural communities becoming cut off, the forecaster said.
The snow will ease later in the day on Thursday, and may turn back to rain or drizzle, especially in the south and east of the area.
The snow will turn into sleet and rain towards the end of the warning period from the south.
Further warnings for ice could also be issued later in the week as temperatures drop below average for this time of year, the forecaster said.
