Other facts from our historical weather data: Which is the warmest month in Stafafell? July has an average maximum temperature of 12°C (54°F) and is the warmest month of the year. Which is the coldest month in Stafafell? The coldest month is December with an average maximum temperature of 3°C (37°F). Which is the wettest month in Stafafell? October tops the wettest month list with 227mm (8.9 in) of rainfall. Which is the driest month in Stafafell? May is the driest month with 96mm (3.8 in) of precipitation. Which is the sunniest month in Stafafell? May is the sunniest month with an average of 172 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.