July in Stornoway is the warmest month of the year. In July, the weather in Stornoway is typically warm. Average daily high temperature in July is about 14 degrees above zero. On average, Stornoway has 24 rainy, 4 sunny, 2 cloudy, and 1 partly cloudy day in July. The rains are usually heavy. July as well as January, February, March, and April is considered the most uncomfortable time to visit Stornoway.