Heavy snow is expected in parts of Scotland, with forecasters warning of blizzard conditions and bitterly cold temperatures.
The Met Office issued alerts for central Scotland, Tayside, Fife, Grampian, the Highlands and the Borders, where 4in-8in (10cm-20cm) of snow was expected to fall, accompanied by strong to gale-force winds in some areas.
People should be prepared for the risk of disruption to travel and power supplies as temperatures hover around the freezing mark, forecasters said.
Several roads were closed in the Grampian area, including the A941 Dufftown to Rhynie route and the B974 Banchory to Fettercairn road. The A93 Aboyne to Ballater route was passable with care.
Elsewhere, there were warnings of high winds on the Forth Road Bridge. Drivers were advised to be aware of reduced visibility, obscured road markings and the risk of ice patches.
Rail routes remained unaffected but there were several flight cancellations between London City, Heathrow and the East Midlands to Aberdeen, Glasgow and Edinburgh Airports.
In the Borders, where council officials held a teleconference with Met Office advisers this morning, more than a dozen schools were closed. The Strathclyde Police area is expected to escape the worst of the winter weather, with "occasional snow" and temperatures around 2C (35.6F).
Holyrood Transport Minister Keith Brown said: "Motorists and public transport users should factor the weather and high likelihood of disruption into their travel plans, staying abreast of live travel information by listening to local radio reports and checking online sources.
"While we have implemented a raft of improvements ranging from higher than ever salt stocks to a strengthened fleet of gritters, the public must play their part by making full use of the vast sources of communications available.
"Drivers should take the road conditions into consideration, leaving extra time for journeys if necessary. I would urge the public to stay vigilant and tuned to local radio reports and the Traffic Scotland website as circumstances could quickly change."