Deputy First Minister John Swinney has praised the public for heeding travel warnings as well as helping out anyone stuck in the snow.

He told Good Morning Scotland: "This has been the most significant snow incident we have had since 2010 and it is the first time we have ever had a red warning for snow that has been applied.

"The warning system is very important and since Monday we have been pressing very clearly the strongest possible advice that we were going to face a very severe snow incident over the course of Tuesday, Wednesday and Thursday and that is exactly what we are experiencing.

"It has put the systems, the infrastructure of the country under great stress.

"There are members of the public who have been inconvenienced, there are also members of the public who are going the extra mile.

"I warmly thank individuals who have made that contribution and I also appreciate the way in which members of the public have responded so strongly to the warnings we have issued and have reduced the volume of traffic that has been on the roads over the last couple of days."

Police in Dumfries and Galloway have said they expect further problems on the region's road network throughout the day.

Ch Insp Stuart Davidson said: "We are still in an amber weather warning for the east and mid and upper Nithsdale so it is obviously a good chunk of our region.

"The message is to avoid travel until further notice for these particular areas.

"Whilst some of the roads may seem passable with extreme care it is just actually getting to these main routes that will be the main difficulty in our rural area.

"To the west of the region it is positively spring-like in some areas further towards Stranraer but they have got to remember as they travel east there will be significant disruption in our region today."

Alex Downie from Dundee is stuck on the M80 near Castlecary and has been since 5pm yesterday - 15 hours.

He is driving a loaded HGV with plenty of provisions but is stuck next to a Megabus full of people.

Mr Downie told BBC Scotland: "A few volunteer people came up and down the road about 1am this morning and also a gentleman came over his fence and came down with a bag of provisions."

"The police came down at 4 this morning and advised us we would be moving soon but that's the last I heard."

Virgin Trains is not running any trains between Carlisle and Scotland and there are no replacement buses.

The West Coast mainline operator said it did expect to reopen later today.

It said: "The first northbound train to Scotland is expected to be the 1030 from London, with the first southbound departure expected to be the 1340 from Glasgow.

"Due to the continued uncertainty over the weather, ticket restrictions for passengers travelling to or from Scotland have been relaxed.

"Customers with tickets to or from Edinburgh / Glasgow from Wednesday 28th February to Sunday 4th March (inclusive) can travel on any of our Scotland services during that time."

"Please check our website for details of trains before going to the station. Alternatively, if customers would prefer to cancel their journey, refunds will be given without any fee being charged."

Transport Minister Humza Yousaf said: "The travel advice in the affected areas today could not be clearer - do not travel unless it is absolutely necessary to do so.

"Even after the red warning is lifted, large parts of Scotland will still be subject to high-level amber weather warnings for snow.

"This should not be under-estimated.

"An amber warning means there is a real possibility that vehicles and drivers will become stranded - something that we have already seen happen during this period of snow."

Andrew Anderson
BBC Scotland

We have just stopped at junction 9 which is as far down the M80 as we can go, we are at Stirling services - quite an unpleasant journey at times down from Perth with blizzard conditions at Dunblane at one point.

This has been the pinch point, this was the worst affected area over the last 24 hours with some 1,000 vehicles stuck last night, an eight-mile tailback in both directions at Castlecary.

They got the vehicles moving and then they got stuck again around the Denny area.

Image source, PA

So police have closed the M80 south of junction 9 as they try to get those vehicles moving again.

Where I am there are a number of HGVs that have pulled off the road to wait for conditions to improve.

The advice from police, yet again, is don't travel in the red zone area unless you absolutely have to.

And if you do get stuck please stay with your vehicles because it will just make matters worse if they can't get vehicles off the road. So we are not out of the woods yet.

Stein Connolly at the Transport Scotland control room says they are working hard to get the M80 motorway reopened. About 300 drivers have been stranded overnight on the motorway between Cumbernauld and Bonnybridge.

Mr Connolly said there was a "managed closure" on the M80 from junction 4, Low Wood, to junction 8, Bannockburn.

He said: "The idea of that is it allows our vehicles to go in the opposite direction to allow these stranded vehicles to get moving and then we can grit and plough in front of them.

"That will allow safe passage once we get that done and get the vehicles moving again.

"There are still a considerable number of vehicles in there."

A statement from Edinburgh Airport said: "Travel conditions in Scotland this morning mean that the airport and airlines do not have the critical mass of staff needed to run operations securely.

"The airport is therefore closed until this position is reviewed at 10:00 today.

"We ask that passengers do not come to the airport unless their airline has confirmed that their flight is scheduled. The safety of our passengers and our staff are our priority, and we ask people to make safe decisions regarding their travel."

Glasgow Airport has already said it will be closed until at least 3pm.

Sam spent the night on the M80 near Cumbernauld. He says traffic just ground to a halt.

He said: "I was driving back from north of Inverness down to Harrogate. We left at 2.15 yesterday and we are still north of Glasgow.

"Luckily we are in a works van so the engine has been running all night, trying to stay warm.

"We've had some of the locals jumping over their back fences on to the motorway to offer help."

A Met Office red warning - its highest level - remains in place across a slice of Scotland until 10:00 today.

Image source, Met Office

However, once it is lifted, an amber warning will continue for many parts until 18:00 with a yellow alert until almost midnight for most of the country.

And, after that, most of Friday and Saturday see a yellow warning for much of eastern Scotland.

Stein Connelly from Transport Scotland said there had been about 1,000 cars stranded on the M80 near Cumbernauld but emergency teams managed to "release" about 700 during the night before the weather closed in again.

He told BBC Scotland: "You will have heard the stories about the 1,000 people stuck on the M80. We got it open and we released approximately 700 of those and then with the blizzard conditions we lost it again, with vehicles struggling to get traction. So it closed again and we've been working on that since.

"The weather does not look as if it is going to let up at all. We are still putting the message out, for today avoid travel."

Police Scotland advice for today 'don't travel unless you're an emergency worker'.

There is a RED WARNING in place across most of central Scotland - Glasgow, Edinburgh, much of the Lothians, the northeast Borders, as well as parts of Fife, Perth and Kinross, Forth Valley, North Lanarkshire, Renfrewshire and Dunbartonshire.

The red warning is expected to end at 10 this morning but amber warnings will REMAIN across much of Scotland throughout the day.

Motorists are being advised to avoid the M80 and the M876 around junction 8 - many motorists are stranded.

The police advice is STAY IN YOUR VEHICLE if you're stuck.

The M80 is closed in both directions between between Junction 4a Low Wood and Junction 9 Bannockburn.

The M876 is also closed to northbound traffic after Junction 1 Checkbar,

The Forth Road Bridge is closed in both directions

High winds around the Tay Road Bridge.

There are cancellations affecting almost all Scotrail routes.

The ONLY services running on the ScotRail network this morning are: Aberdeen - Inverness Aberdeen - Dundee Inverness - Kyle of Lochalsh & Wick Inverness - Perth.

No flights to or from Glasgow Airport until 1500 today.

More snow is forecast during throughout the day.

Most airlines have cancelled their operations from Edinburgh Airport until lunchtime.

Prestwick Airport is is open and operational though - as is Aberdeen Airport.

Kawser Quamer
BBC Weather

Severe weather will continue throughout the day today.

In fact, for the next few days we are going to continue to see that feed of bitterly cold air coming in from the east, drawing in those lines of heavy snow showers.

The red warning - the take action warning - is in force across most of the central belt, up into parts of Fife, that's until 10:00.

There are amber be prepared warnings further towards central, southern and eastern parts but a wider yellow be aware warning for most of the country as we are expecting those snow showers to cause some disruption - in the red area potentially another 30cm (12in) of snowfall over the next 24 hours.