The river flows in the southwest area of Java with a predominantly tropical rainforest climate (designated as Af in the Köppen-Geiger climate classification).[3] The annual average temperature in the area is 26 °C. The warmest month is October when the average temperature is around 28 °C, and the coldest is January, at 25 °C.[4] The average annual rainfall is 2970 mm. The wettest month is December, with an average of 475 mm of rainfall, and the driest is September, with 22 mm of rainfall.[5]
