January in Monrovia is the sunniest and the hottest month of the year. In January, the weather in Monrovia is typically hot. Average daily high temperature in January is about 28 degrees above zero. On average, Monrovia has 19 rainy, 7 sunny, 3 partly cloudy, and 2 cloudy days in January. The rains are usually moderate. January as well as February, March, April, and May is considered the most uncomfortable time to visit Monrovia.