Other facts from our historical weather data: Which is the warmest month in Geilo? 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 Geilo? The coldest month is February with an average maximum temperature of -3°C (27°F). Which is the wettest month in Geilo? July tops the wettest month list with 100mm (3.9 in) of rainfall. Which is the driest month in Geilo? April is the driest month with 61mm (2.4 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.