Weather will likely play an important role when you plan your trip to Gjemnes, 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 12°C, while the coldest months are January and February, with an average of 1°C. The rainiest months in Gjemnes are October, September, December and March, with each month seeing an average of 192 mm of rainfall.