The maximum temperature in Geilo is on average 3°C over the year, with values generally ranging between -7°C in January and 16°C in July. About 983 mm of precipitation falls per year, with a minimum of 46 mm in April and a maximum of 115 mm in August.
The climate is suitable for a trip to Geilo in: June, July and August. Nevertheless, the months when the weather is really pleasant are July.
For winter sports and snow, the best months are January, February, March and December.
For hiking and trekking, the best months are May, June, July and August.
In terms of crowd levels, the quietest periods are in January and November, while crowding is high in June, August and July.