The Met Office has issued a red warning for snow for parts of central Scotland
The extreme weather warning runs from 15:00 on Wednesday until 10:00 on Thursday.
People are being advised not to travel in the worst affected areas unless absolutely necessary
Most schools in Scotland are closed on Wednesday and Thursday
Glasgow Airport is closed and buses and trains in the red warning area have stopped
Giancarlo Rinaldi
South Scotland reporter, BBC news website
Scottish Borders Council has shut all its 71 schools due to heavy snowfalls, a move affecting about 15,000 pupils in the region.
It said it was "likely" that they would all remain closed on Thursday as well.
In neighbouring Dumfries and Galloway, a large number of schools have also been shut in the east of the region.
A spokesman for Virgin Trains on the West Coast route said: “Due to the weather, the route between Carlisle and Scotland is closed with no trains, or replacement buses, running.
"Alternative rail routes between England and Scotland are also severely disrupted.
"We will let customers know if Network Rail can reopen the route, but customers should assume there will be severe disruption for the rest of today.
"Customers who wish to postpone their journeys and travel tomorrow can do so – tickets will be valid. Alternatively, if customers would prefer to cancel their journey, refunds will be given without any fee being charged.”
Most schools across Scotland have been forced to close as the country has been swept by snow.
Glasgow Airport flights are affected, so too are Scotland's bus and rail networks.
Scottish Transport Minister Humza Yousaf said it was a "difficult day".
He told BBC Radio Scotland's Good Morning Scotland programme: "What we have seen is, which is a positive, is a reduction in the number of people travelling."