Mountain rescue teams have been sent to check on stranded drivers and Traffic Scotland said gritters were working hard to clear routes at Millbank and Beattock.

Dumfries & Galloway Virtual Operations Support Team, who were set-up to respond to weather in the region, advised against travel.

They added: "We have tasked Moffat Mountain Rescue Team to attend and check on those drivers stuck in their vehicles. We are working to clear the stuck vehicles and clear the crashes.

"Please remain in your vehicle and signal the mountain rescue team or police if you need any help or contact us via 999.

"We advise against all travel however if you do decide to travel you are likely to experience significant delays."

Motorist Nigel Cliff was caught in the jam said: “It is pretty rough”.

Speaking to BBC Scotland, he said: "It's snowing again now so it is probably only going to get worse. There are cars and lorries just sitting here - nothing moving.

"I've got food. I've got big thick coats, big thick socks. My wife always makes sure I've got everything in the car."

Traffic Scotland said: "M74 N/B J15 - J14 Now moving slowly but snow falling heavily so take care and drive to conditions."

Two more gritters and tractors have been sent to assist further.

The Isle of Sky’s A87, its main road, was blocked for several hours in both directions after a lorry jack-knifed.

Two school buses with pupils who were stuck for hours had to return to Portree High and the school said they would be put in temporary accommodation for the night.

The Met Office has issued an amber alert for South West Scotland and parts of the central belt which will last until 08:00am Wednesday.

Scotland’s Transport Minister Humza Yousaf said the number of HGVs "lost traction with challenging weather impacting on M74".

He added: "Necessary to close the junction to get additional gritters and equipment to the scene."

More than 100 schools and nurseries were closed on Tuesday across Scotland with more than 10,000 pupils missing classes.

Snow also affected other parts of the UK ahead of Storm Fionn.

There were extreme travel delays on the M62 between Liverpool and Leeds.

West Yorkshire Police tweeted: "The snow is causing severe disruption on the M62 Westbound towards Manchester very slow from junction 25 to junction 22.

"Take extra care, keep your distance and take warm clothing just in case of an emergency."

Highways England have even said that some motorists were left stranded by the snow and the ice on the motorway.

Up to 80mph gales are set to lash the UK from Wednesday afternoon, with western coastal areas worst affected.

Thousands of families in the south-west are said to have sandbags at the ready following the trail of destruction left in Storm Eleanor’s wake.

A Met Office yellow weather warning for wind has been issued for the majority of the UK from 9pm on Wednesday night up until 11am on Thursday.

It said: "Very strong winds will affect parts of the UK during Wednesday night and into Thursday.

“Injuries and danger to life from flying debris are possible, along with some damage to buildings.