The river flows in the northern area of Papua with predominantly tropical rainforest climate (designated as Af in the Köppen-Geiger climate classification).[7] The annual average temperature in the area is 21 °C. The warmest month is October, when the average temperature is around 22 °C, and the coldest is January, at 18 °C.[6] The average annual rainfall is 4938 mm. The wettest month is March, with an average of 586 mm rainfall, and the driest is October, with 269 mm rainfall.[8]
^Kamholz, David. 2012. The Keuw isolate: Preliminary materials and classification. In Harald Hammarström and Wilco van den Heuvel (eds.), History, contact, and classification of Papuan languages, 243–268. Special issue of Language and Linguistics in Melanesia. Port Moresby: Linguistic Society of Papua New Guinea.
