July in Peoria is the cloudiest and the hottest month of the year. In July, the weather in Peoria is typically hot. Average daily high temperature in July is about 36 degrees above zero. On average, Peoria has 19 sunny, 11 partly cloudy, and 1 rainy day in July. The rains are usually light. July as well as June and August is considered the most uncomfortable time to visit Peoria.