Severe gale-force winds with gusts of up to 90mph have hit parts of Scotland.
Heavy rain was forecast into Thursday and could cause “severe disruption” in combination with the wind, the Met Office said.
It has issued amber “be prepared” warnings of wind for the Highlands, Western Isles and Strathclyde, and less severe yellow “be aware” warnings for the rest of Scotland.
Gusts of 70-80mph are expected in the amber warning area, and to around 90mph in some of the more exposed locations in western Scotland and the Western Isles.
The Met Office has also issued yellow warnings of rain for the Highlands, Western Isles, Strathclyde, Central, Tayside, Fife, South-West Scotland and Lothian and Borders.
Transport Scotland said it is closely monitoring the situation along with its partners, including the local authorities, the Scottish Environment Protection Agency and Police Scotland, to ensure they are prepared for the conditions.
Traffic Scotland operator manager Stein Connelly said: “The Met Office is telling us that the north-west Highlands and Western Isles are likely to face disruption due to the strong winds this evening and into Thursday.
“We would advise people in these areas to prepare for some travel disruption and to allow extra time for their journeys. They should also check the relevant websites for up-to-date travel information.
“Transport Scotland is in regular contact with the Met Office, Police Scotland operating companies and Network Rail as well as the ferry operators and will activate our Multi Agency Response Team through the night to cover the morning peak to ensure the maximum response to any incidents caused by the high winds.”
Forecasters predicted that the weather would be at its worst overnight.
Chris Burton, a forecaster with MeteoGroup, said: “A storm system is moving in off the Atlantic towards the north-west Highlands. It’s really through this evening and overnight that the winds are going to be at their strongest. Most of Scotland will see gusts of 50-70mph and north-west Scotland and the western and northern isles could see gusts of 90mph in some places, so there will be some damaging gusts of wind for a time.
“There’s also going to be some quite heavy rain that will sweep in, and following behind there will be colder air so we could see some wintry showers with snow on higher ground.”
The weather is expected to remain wet and windy in the run-up to Christmas.