July in Carnarvon is the coldest month of the year. In July, the weather in Carnarvon is typically warm. Average daily high temperature in July is about 21 degrees above zero. On average, Carnarvon has 25 sunny, 5 partly cloudy, and 1 rainy day in July. The rains are usually light. July as well as May, June, August, and September is considered the most comfortable time to visit Carnarvon.