Visiting local bars in Surnadal is more fun when the weather is good. These temperatures and rainfall averages can help you decide the best time for bar-hopping. The hottest months are usually July and August, with an average temperature of 12°C, while the coldest months are January and December, with an average of -4°C. The rainiest months in Surnadal are September, October, March and December, with each month seeing an average of 184 mm of rainfall.