Several vehicles have crashed on a motorway as freezing rain and ice created treacherous driving conditions.
Police in Dumfries and Galloway said “multiple” crashes have been reported on the M74 between junction 15 Moffat and junction 17 Lockerbie.
The force urged motorists to drive with caution in the area.
Police tweeted: “Multiple RTC’s being reported on #M74 between Junction 15 #Moffat and 17 #Lockerbie. Road described as very icy with multiple vehicles crashed.
“It appears the freezing rain may have arrived on the motorway.”
Meanwhile, Traffic Scotland tweeted that heavy snow is causing “treacherous conditions” on the A9 and warned people to expect delays between Perth and Aviemore.
The snow gates have been closed in both directions at Braemar and northbound at Spittal of Glenshee.
The Met Office has upgraded its weather warning of ice to amber level and indicated that heavy snow with blizzards could lead to travel delays and power cuts across parts of the country.
The warning, covering the central belt, southern Scotland, Tayside and Fife, is in force until 6am on Sunday.
A yellow warning of snow and ice is in place across most of Scotland until 9am on Sunday, warning that periods of freezing rain could lead to some dangerous travelling conditions.
Police Scotland said people should only travel if they consider it necessary.
In a statement the force said: “Winter driving is a question of common sense and all drivers should ask themselves if they really need to travel when conditions are poor.
“No-one should ever place themselves at risk on the road and it may be worth making alternative arrangements such as delaying travel until conditions improve, or using public transport.
“If you are travelling on the roads you should ensure you and your vehicle are adequately prepared for the conditions, making sure you have sufficient fuel and supplies such as warm clothing, food and water in the event you are delayed for several hours.
“Charge your mobile phone and plan your route as well as alternative routes.”
Following a meeting of the Scottish Government’s Resilience Room on Friday, Transport Minister Michael Matheson said delays and cancellations on public transport were possible.
There could also be interruptions to power supplies and telephone networks, and some rural communities may find themselves cut off.
Mr Matheson said: “I would encourage people in the affected areas to consider whether they need to make their journey. If they do, they should expect disruption.
“Drivers should plan their routes, leave plenty of time, follow Police Scotland travel advice and drive to the conditions.”