January in Fort Worth is the coldest month of the year. In January, the weather in Fort Worth is typically warm. Average daily high temperature in January is about 14 degrees above zero. On average, Fort Worth has 15 sunny, 8 partly cloudy, 6 rainy, and 2 cloudy days in January. The rains are usually moderate. January as well as May, June, July, and August is considered the most uncomfortable time to visit Fort Worth.