Scotland & the UK records its lowest temperatures in 25 years overnight of -23C
The Met Office says an overnight temperature of -23C (-9.4F) recorded in Scotland is the lowest in more than 25 years.
It was the lowest February temperature since 1955, and the UK's coldest night since 30 December 1995.
A Met Office yellow snow and ice warning is in place for large parts of the country until 12:00 on Friday.
ScotRail said the winter weather was causing major problems for its services on Thursday morning.
it's over the last couple of nights the temperature has got really low, especially in northern Scotland.
There are three reasons for this: thick snow on the ground, clear skies and light winds
So when night falls, where the ground would normally radiate heat to the air, that heat can't get out so the air temperature is lower," he explained
If skies are clear, any heat that does get out of the ground, escapes into space
Malcolm MacIntyre, of the Braemar Mountain Rescue Team, told BBC Radio's Good Morning Scotland: "It is a beautiful morning actually and it is really cold.
"The snow is squeaky, which always signifies that it is really cold.
"But in some ways once it gets below about minus 10/12, as long as it is not windy, it just feels really crisp and clear."
Snow from space Today's satellite image shows plenty of snow on the ground across much of Scotland and eastern England under clear skies today
Scottish Water said it was dealing with double the normal number of burst pipes for the time of year as temperatures plunged.
Hundreds of burst pipes have been reported in the past week.
About 29,000 properties were left without water on Wednesday night in the east end of Glasgow after a mains pipe burst.
Scottish Water has also brought in divers to break up ice in reservoirs at Stornoway on Lewis and Kinlochbervie in the Highlands. The build-up of ice was affecting supplies.
The company said it had not previously used so many divers in a such a short period of time.
You can find all the latest weather warnings and forecasts by downloading our app from the google play store by clicking below