The A9 between Inverness and Aviemore has reopened after heavy snow closed the route.
The section of road south of Inverness was shut for most of the morning with reports of lorries stuck in snow.
Meanwhile, more than 60 schools in the Highlands were closed to staff and pupils because of the weather.
Inverness Airport reopened at 1000 GMT after the runway was closed for a time by snow, and rail services have been disrupted.
Amid the disruption, police said they have had reports of motorists removing road closed signs on routes affected by heavy snow.
Sgt Kevin Marshall, of Northern Constabulary, said warning signs were placed on roads for good reason.
'Don't do this'
He said: "If a road is closed it is that - it's closed.
"We have had reports that some signage has been removed from the roads by motorists. I would urge that they don't do this."
Police have also advised motorists to drive with care if they deem their journeys necessary.
A police spokesman said: "Many other areas in the Northern Constabulary mainland area, particularly Caithness, are severely affected by snow and police are advising motorists not to travel unless their journey is absolutely necessary."
A convoy system is now operating on the snow-covered A9
The A96 - the main route between Inverness and Aberdeen - was shut in Aberdeenshire.
Highland Council has listed school closures on its website. Thousands of staff and pupils were told to stay at home.
Meanwhile, Inverness and Wick airport were closed for a time because of the weather, but later reopened.
Campbeltown in Argyll was expected to be closed for a time, but Stornoway, Barra and Benbecula were open.
ScotRail said services between Perth and Inverness were subject to delay, while services between Inverness to Aberdeen were only going to Elgin and only as far as Inverurie coming from Aberdeen.