document: Winds gusting to up to 75mph have been forecast for Tuesday.
  The Met Office has issued a yellow "be aware" warning to cover from 10:00 to 18:00 on Tuesday for the worst affected areas.
  It has warned of the possibility of disruption to ferries, large waves and heavy showers.
  The Met Office said the stronger winds would be "short lived in any one location".
  But it added: "At the same time some large waves will run onto exposed coasts bringing the chance of some spray and wave overtopping."
summary: The Met Office has issued a high winds warning for Shetland, Orkney and parts of the Western Isles and northern mainland Scotland.