The Hebrides have a cool temperate climate that is remarkably mild and steady for such a northerly latitude, due to the influence of the Gulf Stream. In the Outer Hebrides the average temperature for the year is 6 °C (44 °F) in January and 14 °C (57 °F) in summer. The average annual rainfall in Lewis is and sunshine hours range from 1,100 – 1,200 "" (13%). The summer days are relatively long, and May to August is the driest period.