If you're looking forward to lots of outings with your partner, take a look at these details about year-round temperatures in Vik I Myrdal: The hottest months are usually July and August, with an average temperature of 9°C, while the coldest months are December and January, with an average of -1°C. The rainiest months in Vik I Myrdal are September, February, October and January, with each month seeing an average of 231 mm of rainfall.