Other facts from our historical weather data: Which is the warmest month in Kopervik? August has an average maximum temperature of 18°C (64°F) and is the warmest month of the year. Which is the coldest month in Kopervik? The coldest month is February with an average maximum temperature of 6°C (43°F). Which is the wettest month in Kopervik? October tops the wettest month list with 233mm (9.2 in) of rainfall. Which is the driest month in Kopervik? May is the driest month with 92mm (3.6 in) of precipitation. Which is the sunniest month in Kopervik? May is the sunniest month with an average of 226 hours of sunshine. 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.