LIVE: Met Office yellow wind warning in force as trees and power cables come down Wind is causing havoc in parts of Devon and Cornwall this morning as the yellow weather warning for wind continues to bring blustery conditions to the South West The video will auto-play soon8Cancel Play now Power cables have come down in Cornwall and trees have been blown over in Devon this morning as a yellow weather warning for wind issued by the Met Office continues to bring blustery conditions to the region. The Met Office weather warning, which spans the whole of Devon and Cornwall, Wales and the south east will be in place until 9pm tonight, Friday, after coming into force at 3pm on Thursday.