Snow chaos: Scotland braces for day two of red alert
The warning, meaning danger to life, is in place across the central belt until 10am.
Scotland is bracing itself for another day of chaos, with a red snow warning in place until Thursday morning.
The red alert, meaning danger to life, is in force until 10am across the central belt, covering areas including Edinburgh, Glasgow and Dunfermline.
More than 20 councils have shut all its schools on Thursday, while others are yet to announce their closures.
It means around 450,000 pupils will stay at home, making it the biggest period of education disruption in years.
Passengers, who have been left stranded at Glasgow Airport overnight, are expected to face further disruption throughout the remainder of the week.
Bosses have announced there will be no flights in or out of the airport until 11am on Thursday at the earliest.
A spokesman said: "We would advise passengers not to travel to the airport and anyone with travel plans should contact their airline directly for specific flight information."
EasyJet has already announced it has cancelled all flights going to Glasgow on Thursday.
The Red Cross has delivered camp beds and blankets for those who are staying overnight due to the disruption.
ScotRail has warned all services in the central belt will be suspended until "at least late morning on Thursday".
Services on four routes will be resumed when it is safe to do so.
These are Perth-Inverness, Dundee-Aberdeen, Aberdeen-Inverness and Inverness-Wick/Thurso. For all other services, travellers are advised to check ScotRail's website or social media before setting off.
In a statement, the operator said: "A red weather alert has been issued by the Met Office. Passengers are advised not to travel in the affected areas.
"The safety of staff and customers is our priority, which is why services in the red area are suspended."
Hospital appointments have also been cancelled across Scotland.
STV weather presenter Sean Batty said: "As much as 40cm of lying snow is expected by tomorrow morning.
"We wil have an additional 10 to 15cm tonight.
"The drifting and blowing of powdery snow could completely cut off areas.
"Please, if you are in the red area, stay indoors and only head out if you really, really have to.
"This really is a truely, exceptional spell of wintry weather which will continue through the night and into tomorrow morning.
"Unfortunately, the cold air is here to stay until next week."
Commuters have been warned to stay clear of travelling, with miles of tailbacks expected on routes including the M80 and Edinburgh city bypass.
On Wednesday, motorists on the city bypass could be seen driving in the wrong direction to beat the traffic.
Superintendent Helen Harrison said: "I would urge everyone to consider if they have to travel in the areas affected by the red and amber warnings.
"The red warning is the highest that the Met Office issues and is not taken lightly - it indicates conditions will be treacherous with drifting and lying snow, winds creating blizzard conditions and very low temperatures.
"Many people have been making arrangements to leave work early but with conditions so poor we still expect rush hour to be busy so if you can avoid travelling please do so."