In May, the weather in Riva del Garda is typically warm. Average daily high temperature in May is about 14 degrees above zero. On average, Riva del Garda has 22 rainy, 5 partly cloudy, and 4 sunny days in May. The rains are usually heavy. May as well as April, June, July, and August is considered the most uncomfortable time to visit Riva del Garda.