The first named storm of the season, Storm Otto, is forecast to batter parts of Scotland and England on Friday.
The Met Office said winds of 60-70 mph were likely – as high as 80mph on exposed coasts in northern Scotland.
A yellow warning has been issued from 03:00 to 15:00 for almost all Scotland and another from 05:00 to 14:00 for the Borders and north east England.
Potential impacts include large waves on North Sea coasts as well as a chance of some damage to buildings
Ferry operator CalMac has already warned customers of disruption to services between Scotland’s west coast mainland and islands.
The Mountain Weather Information Service described it as a powerful Atlantic storm, warning that upland areas from Scotland to the Pennines could see gusts of up to 100mph.
The storm has been named Otto by the Danish Met Office. The UK Met Office has adopted the same name.
It is the first named storm to hit the UK since Franklyn last February. The Met Office’s season for named storms runs from September to September, and the names are given to raise awareness of severe weather.
Chief meteorologist Andy Page said: “Storm Otto will bring high winds and rain to the UK, with some northern parts of Scotland and the northeast of England likely to get the strongest gusts of wind, possibly in excess of 75mph.
“Warnings have been issued and could be updated as Storm Otto develops.
“There’s a chance of travel disruption and high-sided vehicles could be particularly prone to disrupted plans in this set-up. There’s associated rain with Storm Otto, with 40-50 mm of rain likely to fall over parts of western Scotland.”
Earlier this month, flights and ferry services in the Highlands and Western Isles were disrupted by 75mph winds.