January in Nairobi is the sunniest month of the year. In January, the weather in Nairobi is typically warm. Average daily high temperature in January is about 24 degrees above zero. On average, Nairobi has 13 partly cloudy, 10 sunny, 5 cloudy, and 3 rainy days in January. The rains are usually light. January as well as February is considered the most comfortable time to visit Nairobi.