January in Kennesaw is the windiest and the coldest month of the year. In January, the weather in Kennesaw is typically cold. Average daily high temperature in January is about 9 degrees above zero. On average, Kennesaw has 14 sunny, 9 rainy, 7 partly cloudy, and 1 cloudy day in January. The rains are usually heavy. January as well as February, July, August, and December is considered the most uncomfortable time to visit Kennesaw.