Weather is probably a major factor when you plan your trip to Giske, but bear in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually August and July, with an average temperature of 13°C, while the coldest months are February and January, with an average of 3°C. The rainiest months in Giske are October, September, December and January, with each month seeing an average of 258 mm of rainfall.