May in Iwonicz-Zdroj is the rainiest month of the year. In May, the weather in Iwonicz-Zdroj is typically warm. Average daily high temperature in May is about 17 degrees above zero. On average, Iwonicz-Zdroj has 19 rainy, 10 sunny, and 2 partly cloudy days in May. The rains are usually heavy. May as well as February, March, April, and November is considered the most uncomfortable time to visit Iwonicz-Zdroj.