Planning for the weather is an important factor for making your trip to Ullensvang a success, especially when you’re splurging. The hottest months are usually July and August with an average temp of 50°F, while the coldest months are January and February with an average of 23°F. The rainiest months in Ullensvang are December, October, January, and September, with each month seeing an average of 12 inches of rainfall.