Forecasters have upgraded snow weather warnings from yellow to amber in some parts of the UK.
Yellow alerts are in place in other areas, as people face a wintry start to 2026.
Amber warnings for heavy snow showers in parts of Scotland have been issued by the Met Office.
They are in place from midday on Friday to midday on Saturday.
Snow could bring disruption to parts of northern Scotland. The areas covered in the amber warnings include Angus, Perth and Kinross, Aberdeen, Aberdeenshire, Moray, and the Highlands.
Around 10-20cm of snow is likely at low levels, with 30-40cm possible on high ground, while winds could lead to temporary blizzard conditions, according to the Met Office.
It added that some delays and cancellations to rail and air travel are likely, as are power cuts and disruption on the roads, while some rural communities may be cut off.
Meanwhile, there is a yellow warning for snow and ice on Friday across large parts of England and Wales, including Chester and Greater Manchester down to London and Kent.
The warning lasts from midnight to noon.
Snow up to 5cm could cover some areas, especially on higher ground in parts of North Wales and northwest England.
Separate yellow warnings are in place for Northern Ireland between midnight and 10am on Friday.
Weather warnings are already in force on Thursday in Scotland, with a yellow warning of snow and ice covering the northern part of the nation.
The Met Office has said there could be 2-5cm by the evening, with 10cm accumulating by Friday morning, while up to 20cm could build up above 200 metres.
The warning is in force until midnight on Friday and at the weekend it extends further south, covering the area down to Perth and southerly parts of Argyll and Bute until midnight on Sunday.
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Meanwhile, the UK Health Security Agency (UKHSA) has issued health warnings for the start of the year.
It previously issued amber cold health alerts in the North East and North West of England.
However, yellow alerts have been upgraded to amber across the East Midlands, West Midlands, South East, South West, East of England, Yorkshire and the Humber, and London.
These warnings are in place until 10am on 6 January.
The UKHSA said it means the weather is "likely" to cause significant impacts across health and social care services, including a "rise in deaths" among those with health conditions or aged 65 or over.
(c) Sky News 2026: UK weather: Snow warnings upgraded to amber for some areas as country sees wintry start to
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