The river flows in the southwest area of Sulawesi with predominantly tropical monsoon climate (designated as Am in the Köppen-Geiger climate classification). The annual average temperature in the area is 23 °C. The warmest month is October, when the average temperature is around 25 °C, and the coldest is July, at 21 °C. The average annual rainfall is 2550 mm. The wettest month is January, with an average of 404 mm rainfall, and the driest is September, with 29 mm rainfall.
^Salo Welonge at Geonames.org (cc-by); Last updated 2013-06-04; Database dump downloaded 2015-11-27
^Peel, M C; Finlayson, B L; McMahon, T A (2007). "Updated world map of the Köppen-Geiger climate classification". Hydrology and Earth System Sciences. 11 (5): 1633–1644. doi:10.5194/hess-11-1633-2007. Retrieved 30 January 2016.
^ a b"NASA Earth Observations Data Set Index". NASA. 30 January 2016.