Other facts from our historical weather data: Which months have the greatest rainfall in Sunndalsøra? Most rainfall (rainy season) is seen in June, July and August. Which is the warmest month in Sunndalsøra? July has an average maximum temperature of 17°C (63°F) and is the warmest month of the year. Which is the coldest month in Sunndalsøra? The coldest month is December with an average maximum temperature of -2°C (28°F). Which is the wettest month in Sunndalsøra? August tops the wettest month list with 166mm (6.5 in) of rainfall. Which is the driest month in Sunndalsøra? April is the driest month with 103mm (4.1 in) of precipitation. No idea where to travel to this year? We have a tool that recommends destinations based on your ideal conditions. Find out where to go with our weather planner.