Snow, rain and strong winds are due to sweep in today as Storm Doris makes its presence felt around Scotland.
The bad weather is likely to cause travel disruption, damage buildings and send debris flying, forecasters have advised.
Yellow "be aware" warnings are in place for many parts of Scotland, while amber "be prepared" notices are in force on Thursday for snow across the central belt, the Borders, Dumfries and Galloway, Tayside and Fife.
Weather warnings are also in place across most of England, Wales and Northern Ireland.
Coming after a mainly mild February so far, Scotland is expected to be hit by up to 15cm of snow falling "quite widely", with accumulations of 30cm potentially falling on hills above 300 metres.
The strongest winds are forecast across England and Wales on Thursday, but gusts of 50-60 mph are expected widely across the warning area north of the border, with the risk of 70 mph on coasts and hills, the Met Office said.
The Met Office said: "As Storm Doris moves eastwards across central parts of the UK on Thursday, a spell of heavy snow is expected on its northern flank.
"There is some uncertainty over the track of Doris and, therefore, over the extent of snowfall, but confidence is now higher for disruptive snow to affect the amber area.
"Heavy snow is expected on Thursday. Accumulations of 10 to 15cm are likely quite widely, with 20 to 30cm falling on hills above 300 metres.
"This will lead to disruption to transport and perhaps power supplies."
Motorists have been advised to check travel information before they embark on their journey.
Stein Connelly, of Traffic Scotland, said: ''On Thursday the worst of any snow will be on the higher routes, especially in the central and south of Scotland, and we would ask road users to keep this in mind when they are planning their journeys and that they drive according to the conditions."
BEAR Scotland said gritters will be out patrolling the roads.
"As ever, we ask members of the public to ensure their vehicle is well maintained, that they pay close attention to local and national media and information to help plan journeys during inclement weather and that they carry equipment to help themselves should conditions deteriorate," a spokeswoman said.
Storm Doris is the first major winter weather front for two months.
The north of the country was worst affected, with homes losing power when Storm Conor hit on Boxing Day with winds of more than 90mph.
Transport minister Humza Yousaf said: "The Met Office is telling us that Storm Doris will bring a mixture of heavy snow, sleet and rain across central and southern areas and this will lead to poor driving conditions, especially around the Southern Uplands.
"Transport Scotland is working with the relevant organisations, such as Police Scotland and the road operating companies, to try to mitigate the effects of this latest set of wintry conditions, but we would ask road users to be mindful that disruption is likely and to plan accordingly."