May in Bartlesville is the rainiest month of the year. In May, the weather in Bartlesville is typically warm. Average daily high temperature in May is about 26 degrees above zero. On average, Bartlesville has 13 rainy, 11 sunny, 6 partly cloudy, and 1 cloudy day in May. The rains are usually heavy. May as well as January, February, March, and June is considered the most uncomfortable time to visit Bartlesville.