In May, the weather in Chiangmaj is typically hot. Average daily high temperature in May is about 31 degrees above zero. On average, Chiangmaj has 19 rainy, 5 cloudy, 5 partly cloudy, and 2 sunny days in May. The rains are usually heavy. May as well as June, July, August, and September is considered the most uncomfortable time to visit Chiangmaj.