July in Guanajuato is the rainiest and the cloudiest month of the year. In July, the weather in Guanajuato is typically warm. Average daily high temperature in July is about 21 degrees above zero. On average, Guanajuato has 27 rainy, 3 sunny, and 1 partly cloudy day in July. The rains are usually heavy. July as well as June, August, and September is considered the most uncomfortable time to visit Guanajuato.