Members of the public have been urged to stay off the roads, with weather warnings covering much of the country.
Police urged people only to travel if absolutely necessary in areas covered by amber snow and ice warnings.
Officers said there was a “high risk” of disruption and delays on the roads in areas covered by the alert, which is valid until 10pm on Friday.
The M74 saw delays due to the wintry weather and collisions, with travel officers warning other routes across the country could face difficulties over the coming days.
The Met Office said “be prepared” amber warnings cover Tayside, Fife, central and southern Scotland and Strathclyde.
Meanwhile, another yellow alert of snow and ice is in place across Northern Ireland, most of Scotland and northern England until just before midnight on Friday.
Police Scotland urged those who lived within the amber warning to stay off the roads when in.
Superintendent Louise Blakelock, of Police Scotland’s road policing department, said: “If you travel on the road network in the warning area, you will be disrupted and you will face significant delays.”
She added: “I would like to make it clear that there is a high risk of disruption for road journeys and with that comes a high likelihood of the conditions being very poor, therefore I would ask people whether their journey is really necessary?”
Forecasters said there is a chance of power cuts, while some rural communities may be cut off.
Dozens of schools around Scotland are closed while some shut early due to the weather.
The Scottish Government said the Multi Agency Response Team (MART), involving partner organisations such as Police Scotland, is monitoring the situation.
Scotland’s Transport Minister Humza Yousaf said: “With the Met Office issuing another amber warning for snow, we are facing another potentially difficult period for drivers on the trunk road network.
“We’re being told the period between 3pm and 10pm tonight is going to be challenging, so I’m urging people to avoid travel within the amber area at that time.
“More widely, we’re advising people to avoid travel if possible. If you choose to travel, particularly in the evening peak period, you are likely to face significant delays and disruption.
“Consider if you can make your journey home from work earlier than usual. Scottish Government officials are contacting business groups to make them aware of this advice, and I’d also ask employers to be flexible and consider letting staff leave early.
“If you must travel, then please take extra time to plan your journey, listen to police advice and drive to the conditions.”
Some schools in the Borders, South Lanarkshire, Perth and Kinross and the Highlands are closed due to the weather, while North Lanarkshire Council said schools would shut early.
A yellow “be aware” warning of snow and ice for most of Scotland, Northern Ireland and North West England, North East England, Yorkshire and Humber is in force until 11.55pm on Friday.
Saturday will see a similar warning in place just after midnight until 11pm covering much of Scotland, north east England, north west England, Yorkshire and Humber.