Temperatures in parts of the Highlands have plunged as low as -18C overnight as much of Scotland had its coldest night of the winter.
Aviemore recorded the coldest February temperature since 1986 (-18C), Altnaharra in the Highlands was down to -15C and Aberdeen was -12C.
The Met Office warned of freezing temperatures leading to the risk of widespread ice on untreated roads.
Temperatures in Glasgow and Edinburgh were about -1C despite snow falls.
There was more snow over much of southern and central Scotland overnight.
Drivers were being advised to take extra care.
No major routes were closed but in Dumfries and Galloway the M74 was down to two lanes at Beattock Summit.
About 80 Aberdeenshire schools and six schools and a nursery in the Highlands were closed or partially closed as cold weather continued to cause problems.
The freezing conditions provided a boost for Scotland's ski centres over the weekend.
Much of Scotland had its coldest night of the winter
Skiers flocked to the slopes to make the most of the weather.
At Glenshee Ski Centre the car park was full by 1000 GMT, with 1,500 cars parked.
However, some people were reporting that their cars were getting stuck in the snow and Grampian Police was forced to close the snow gates on the incoming roads in an attempt to persuade new arrivals to go elsewhere.
The centre's website said that conditions were "nearly perfect".
At Nevis Range ski centre near Fort William there were about 800 people already on the slopes by 1030 GMT.
The icy conditions made driving difficult in some areas on Sunday and in Grampian the B974 Banchory to Fettercairn road and the B976 Crathie to Gairnsheil roads were closed due to ice and snow, while some roads in the Highlands were also closed.
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