Britain is braced for the arrival of Storm Barbara, with winds of 90mph expected to batter some parts of the country.
Forecasters are warning that wintry showers, strong winds and lightning could lead to disruption to power supplies and travel across the north-west of the UK.
The Met Office has issued severe weather warnings for many parts of Britain, with Scotland expected to bear the brunt of the storm.
An amber “be prepared” wind warning is in place for northern and western parts of Scotland for Friday afternoon, evening and overnight into Christmas Eve.
Two separate Yellow “be aware” wind warnings are in place, one covering northern parts of the UK where gusts of 60 to 70mph are expected quite widely, and one for more southern areas, where a narrow and intense band of heavy rain and gusty winds could lead to some disruption.
Flood alerts are also in place for the Highlands and Western Isles, as well as Skye and the Scottish Borders.
Brent Walker, Met Office deputy chief meteorologist, said: “Storm Barbara is crossing the Atlantic and will pass close to the north-west of the UK during Friday, bringing the potential for some disruption to power supplies and travel, and possibly structural damage.”
The Scottish Government said it is being regularly updated on the expected impact on travel across the country.
The rest of Scotland, pockets of Northern Ireland, north Wales and the north of England are also due to feel the force of Storm Barbara on Friday.
Scotland’s transport minister Humza Yousaf said: “Ministers are getting regular updates on the status of Storm Barbara and the likely impacts, with gusts of 90mph expected across the far north of the country on Friday where the Met Office has an amber warning in place.
“The safety of the travelling public is our main concern and services will run where possible, but planning in advance is essential and people should leave plenty of time for journeys and consider the conditions and when they travel.”
ScotRail said that due to the severe weather conditions forecast, speed restrictions and a small number of service withdrawals will take place as a safety precaution on Friday.
It said that as some trains will be travelling at slower rates, their journey times will be extended and service levels on some lines in the south, west and north will have to be reduced as a result.
South of the border, councils were said to be ‘’fully prepared’’ for the onset of harsh conditions over Christmas.
The Local Government Association (LGA), which represents hundreds of councils in England and Wales, said it was issuing renewed advice on how to deal with flash floods and has stockpiled more than one million tonnes of salt to grit roads.
Environment spokesman Martin Tett said: ‘’Councils are fully prepared to protect residents and minimise disruption caused by Storm Barbara and other potential bad weather such as snow and flooding.
“Council staff will be out in force clearing roads of any debris and damage.’’