UK records coldest March night since 2010
The UK has recorded its coldest March night since 2010 after temperatures in the Highlands fell to -15.4C.
Forecasters said an Arctic blast was responsible for the record lows in Kinbrace.
All schools in Shetland have been shut for the third day in a row due to the wintry weather and there are further closures in Aberdeenshire and Highland.
The Met Office warned snow and ice could cause travel disruption in Scotland through to Friday night.
It also warned the weather could cut off rural communities.
Speaking on BBC Radio's Good Morning Scotland programme, BBC Scotland weather forecaster Joy Dunlop said: "Last night was officially the coldest March night on record in the UK since 2010."
The UK's coldest March night on record was -22.8C on 14 March 1958 at Logie Coldstone in Aberdeenshire.
A series of yellow "be aware" warnings for later this week have been updated since first being issued.
The heaviest snowfalls are expected on Thursday and Friday, but with Friday's warning now covering central and southern Scotland.
A new warning has been issued for Edinburgh, Lothian and the Scottish Borders covering from 17:00 on Wednesday to 07:00 on Thursday. Forecasters said snow could accumulate to 5cm (2in).
Parts of the Highlands had heavy snow overnight, with up to 10cm (4in) falling over Sutherland, according to Highland Council.
Emergency services were sent to a multiple-vehicle crash on the A96 at Dukewell near Huntly in Aberdeenshire at about 07:40.
The road has been closed and police have set up local diversions.
Traffic Scotland warned that low sun glare was an issue in the area.
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The cold conditions follow Scotland's third-mildest February on record, according to provisional statistics.
The south of England and Wales will also be affected by snow and ice over the next few days.
The UK Health and Security Agency has issued a level three cold weather alert for the whole of England lasting until midnight on Thursday.
In January, an amber warning for snow was issued for the Highlands, Western Isles and Orkney and Shetland and the weather closed schools across the north of Scotland.