Weather will likely play an important role when you plan your trip to Ullensvang, and keep in mind that cheaper options are usually available when the weather isn't as good. 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.