May in Pamplona is the rainiest month of the year. In May, the weather in Pamplona is typically warm. Average daily high temperature in May is about 15 degrees above zero. On average, Pamplona has 24 rainy, 5 sunny, 1 cloudy, and 1 partly cloudy day in May. The rains are usually heavy. May as well as January, February, March, and April is considered the most uncomfortable time to visit Pamplona.