The river flows in the southwest area of Papua with predominantly tropical rainforest climate (designated as Af in the Köppen-Geiger climate classification).[2] The annual average temperature in the area is 21 °C. The warmest month is October, when the average temperature is around 23 °C, and the coldest is July, at 20 °C.[3] The average annual rainfall is 5547 mm. The wettest month is May, with an average of 594 mm rainfall, and the driest is July, with 384 mm rainfall.[4]