August in Kotabaru is the sunniest month of the year. In August, the weather in Kotabaru is typically warm. Average daily high temperature in August is about 27 degrees above zero. On average, Kotabaru has 24 rainy and 7 sunny days in August. The rains are usually heavy. August as well as January, February, March, and April is considered the most uncomfortable time to visit Kotabaru.