March in Rexburg is the rainiest month of the year. In March, the weather in Rexburg is typically cold. Average daily high temperature in March is about 5 degrees above zero. On average, Rexburg has 21 rainy, 4 sunny, 3 cloudy, and 3 partly cloudy days in March. The rains are usually moderate. March as well as April is considered the most uncomfortable time to visit Rexburg.