Brits are being warned of heavy snow with a new "risk to life" amber warning issued by the Met Office in Scotland as the freezing temperatures continue up and down the country.
The UK has seen a cold blast this week with snow and ice warnings caused by cold air moving south from the Arctic.
A Met Office amber warning has been put in place for central Scotland that will now run until midday and a yellow warning covers a wider area of the country until 9pm.
There are also snow and ice warnings for the Shetlands until 10am.
Elsewhere in the UK there is also expected to be a hard frost with temperatures dropping to -10C this morning.
The amber warning for Scotland states: "Heavy snow causing disruption on Friday morning."
People have been told: "Travel delays on roads are likely, stranding some vehicles and passengers. Some delays and cancellations to rail and air travel are likely.
"There is a good chance that some rural communities could become cut off. Power cuts are likely and other services, such as mobile phone coverage, may be affected."
Travellers are being told to take extra care this morning, with a number of road closures being reported in the early hours.
"A very cold night out there with a widespread hard frost, temperatures quickly falling away, way below freezing," said Met Office forecaster Craig Snell.
"We will start to see a band of sleet and snow for western Scotland and that will begin to work its way southward as we start Friday morning."
Most of England and Wales is expected to escape the snow but it will remain bitterly cold during the day with temperatures generally close to zero.
Amber warnings mean that there are more severe conditions with a Met Office guide saying people "should think about changing your plans and taking action to protect yourself and your property. You may want to consider the impact of the weather on your family and your community."
The Met Office stated: "Outbreaks of snow are expected to move eastwards across Scotland on Friday. Snow will initially fall to low levels, with 5 to 10 centimetres accumulating in places this morning in two to three hours.
"From late morning, snow at low levels will turn to sleet or rain, but further snow is likely above 200 metres where up to 20 cm may accumulate by afternoon."
Road management firm BEAR Scotland said: "We have gritters out but driving conditions are difficult. Please reduce your speed and take care."
