Sleet and snow has been falling in parts of Scotland and is expected to continue through to Monday.
Snow and ice are affecting many roads across Scotland.
Snow at low levels to depths of 2-6cm has been forecast and could reach 10-15cm on higher ground.
There are problems on the A9 in the Highlands and in Central Scotland and many motorways are badly affected by lying snow.
The Met Office has issued "be prepared" amber warnings for the Highlands, Strathclyde, Tayside and South West.
On the M74 at Lesmahagow in South Lanarkshire some drivers have been stuck for two hours southbound after a lorry jackknifed in the snow.
A jack-knifed lorry on the M8 caused disruption earlier, but Strathclyde Police said both lanes were clear despite snow across the central belt.
Police are urging motorists to be prepared and aware of the risk of black ice.
Tayside Police said it had been dealing with seven minor crashes due to snow and ice, including a horse box that overturned on the M90 near Kinross. Two horses had to be rescued from the trailer.
Transport Minister Keith Brown said all the relevant agencies were working hard to keep Scotland moving.
There have also been some minor accidents in the Grampian and Northern police areas due to the conditions.
But he urged the public to "play their part" by checking weather forecasts and travel information before travelling.
Northern Constabulary said there had also been a loss of 999 call service in the Rosehall area of Lairg in Sutherland, which was affecting 176 telephone lines.
Transport Scotland said its multi-agency response team had been convened to monitor the situation.
This was thought to be due to the weather conditions.
In the Highlands the whole of the A9 is badly affected by snow and ice, especially at Helmsdale, Dalwhinnie and Badenoch.
A spokesman said a back-up system was in place and it was hoped the fault would be fixed later on Sunday.
There are very difficult conditions on the A9 between Tayside and Central region - especially near Balhaldie.
Transport Scotland said its multi-agency response team had been convened to monitor the situation overnight and into Monday's commuter rush hour.
The M8 in North Lanarkshire was partially blocked westbound by an accident near Junction 5 Shotts.
Following a meeting with representatives of the police, rail operators, road operating companies and the Met Office, Transport Minister Keith Brown said gritter patrols had been strengthened.
The M74 in Dumfries and Galloway was down to one lane between Junction 15 Beattock and 16 Johnstonebridge.
He said: "We've already seen some wintry weather across much of Scotland and, while it is not as severe as this time last year, we cannot afford to be complacent.
Mr Brown said gritter patrols had been strengthened.
"With this weather set to continue, a fleet of gritters and winter patrols will be out throughout the night to treat roads where required."
He said: "We've already seen some wintry weather across much of Scotland and, while it is not as severe as this time last year, we cannot afford to be complacent."
He urged the public to "play their part" by checking weather forecasts and travel information before travelling.
Assistant Chief Constable Allan Moffat urged drivers to be aware of the possibility of black ice.
The Met Office warned that icy stretches were likely to form on untreated surfaces, and could lead to travel disruption in places.
The A96 at Nairn was closed following a road traffic collision and a local diversion was in place.
Some routes in Caithness, Sutherland and Ross-shire have been affected by snow and slush. Icy conditions have also been reported in these areas, as well as in Inverness and Nairn.
Snow has been falling on hills and mountains in the area over the past few weeks.
Are you in any of the snow-hit areas of Scotland? Send us your comments using the form below.
Are you in any of the snow-hit areas of Scotland? Send us your comments using the form below.
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