July in Las Vegas is the rainiest and the cloudiest month of the year. In July, the weather in Las Vegas is typically warm. Average daily high temperature in July is about 25 degrees above zero. On average, Las Vegas has 18 rainy, 7 sunny, and 6 partly cloudy days in July. The rains are usually heavy. July as well as January, February, August, and December is considered the most uncomfortable time to visit Las Vegas.