July in Hamilton is the cloudiest and the warmest month of the year. In July, the weather in Hamilton is typically warm. Average daily high temperature in July is about 17 degrees above zero. On average, Hamilton has 17 rainy, 9 partly cloudy, and 5 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 Hamilton.