March in Grand Junction is the rainiest month of the year. In March, the weather in Grand Junction is typically warm. Average daily high temperature in March is about 13 degrees above zero. On average, Grand Junction has 13 sunny, 7 rainy, 7 partly cloudy, and 4 cloudy days in March. The rains are usually light. March as well as January, February, and December is considered the most uncomfortable time to visit Grand Junction.