Hundreds of schools have been closed and there is significant disruption on the road and rail network as a result of heavy snow in Scotland.
Police are urging people not to travel in the amber weather warning area, which covers much of the country.
The weather has led to the closure of the train route between Carlisle and Scotland, with other rail routes between England and Scotland also badly disrupted.
In addition to schools, some universities and nurseries have also been forced to close.
A number of football fixtures have also been postponed.
On the roads, a lorry came off the A90 at Stonehaven in Aberdeenshire and there have been several accidents elsewhere.
Part of the M74 northbound was closed due to “a number of vehicles losing traction”, although it was later reopened, Traffic Scotland said.
The Forth Road Bridge is closed while high winds and wintry showers are making driving conditions difficult on the Tay Road Bridge.
The A93 is shut at Braemar, while some B roads in the Banchory area are closed, as are the snow gates at Tomintoul.
Virgin Trains said the route between Carlisle and Scotland is closed, with no trains or replacement buses running.
Other rail routes between England and Scotland are also “severely disrupted”.
ScotRail advised customers on Wednesday morning not to travel in the Strathclyde area of the country due to the weather conditions.
The operator warned on its website: “Train services running across the whole ScotRail network will be cancelled, delayed or revised. Disruption is expected until the end of the day.”
The weather also affected flights, with Glasgow Airport suspending all services until lunchtime following heavy snowfall.
Stein Connelly, of Transport Scotland, told BBC Radio Scotland: “We’re seeing significant weather disruption on the network, we’ve got all our gritters out and ploughs working right throughout the day, right throughout the night, but we’re still seeing significant challenges.
“The police are advising in the amber area don’t travel on the roads but we’re still seeing busy roads, incidents on them, cars coming off the roads, HGVs blocking and losing traction, and that stops our gritters getting out and on to the roads and keeping it clear, so the message is quite clear – avoid travel on these roads.”
Pupils across the country are enjoying a “snow day” with all schools shut in the East Dunbartonshire Council, City of Edinburgh Council, Falkirk Council, Fife Council, Scottish Borders Council, Stirling Council, and East Renfrewshire Council areas.
Glasgow City Council and Renfrewshire Council have closed all schools and nurseries for the day due to the weather, while West Lothian Council has also shut all schools.
In Aberdeenshire more than 120 schools are shut, while the University of Glasgow and Glasgow School of Art (both its Glasgow and Highlands and Islands campuses) are also closed due to the weather.
In the Highlands, there are at least 47 schools and 25 nurseries closed across the council area.
The universities closed include Glasgow, Stirling and Strathclyde.
The SPFL announced that Wednesday night’s games in the Ladbrokes Premiership – Celtic v Dundee, Hibernian v Hamilton Academical, Motherwell v Aberdeen – have been posponed.
The Met Office amber warning for snow is covering many areas including Central, Tayside, Fife, Grampian, Highlands, Western Isles, south west Scotland, Lothian and Borders and Strathclyde.
The worst-affected areas could see up to 16in (40cm) of snow and a wind chill of minus 10C (14F).
Transport Minister Humza Yousaf has said amber alerts for snow and freezing winds from the early hours of Wednesday could be changed to red for extreme weather in certain areas, with motorists urged not to travel.
A red weather warning means a high potential of “widespread damage”, travel and power disruption and risk to life.
Met Office advice for such alerts is to “avoid dangerous areas and follow the advice of the emergency services and local authorities”.
Met Office meteorologist Aidan McGivern said maximum temperatures on Wednesday would be barely above freezing, feel more like minus 10C (14F)once the wind chill factor is taken into account.