Storm Abigail, the first storm to be officially named by the Met Office, has been upgraded from a yellow warning to amber.
The amber “be prepared” warning covers the Western Isles, Argyll and the Highlands and Orkney.
According to the Met Office winds could gust to up to 90mph and forecasters said large waves could affect coastal areas.
Yesterday’s  yellow “be aware” warning has been updated and extended to cover most of Scotland.
The yellow warning begins on Thursday at 6pm and is set to last until 2pm Friday and the amber warning begins at 9pm on Thursday to non on Friday.
Rain and lightning have also been forecast for the next two days.
Ferry operator Caledonian MacBrayne have cancelled all services for Thursday’s Mallaig to Armadale crossing because of anticipated high winds.
Storm Abigail is the first to be officially named by the Met Office after the forecast service asked members of the public for suggestions in naming storms.
Storm Abigail weather warning upgraded to amber for Scotland