July in Myrtle Beach is the hottest month of the year. In July, the weather in Myrtle Beach is typically hot. Average daily high temperature in July is about 30 degrees above zero. On average, Myrtle Beach has 13 rainy, 12 sunny, 5 partly cloudy, and 1 cloudy day in July. The rains are usually heavy. July as well as January and August is considered the most uncomfortable time to visit Myrtle Beach.