July in Reykyavik is the warmest month of the year. In July, the weather in Reykyavik is typically warm. Average daily high temperature in July is about 13 degrees above zero. On average, Reykyavik has 17 rainy, 6 cloudy, 4 sunny, and 4 partly cloudy days in July. The rains are usually heavy. July as well as January, February, March, and April is considered the most uncomfortable time to visit Reykyavik.