Rokan-kiri River

The river flows in the central area of Sumatra, which has a predominantly tropical rainforest climate (designated as Af in the Köppen-Geiger climate classification).^[3] The annual average temperature in the area is 23 °C. The warmest month is August, when the average temperature is around 24 °C, and the coldest is January, at 22 °C.^[4] The average annual rainfall is 2742 mm. The wettest month is November, with an average of 401 mm of rainfall, and June is the driest, with 85 mm of rain.^[5]

• List of drainage basins of Indonesia
• List of rivers of Indonesia
• List of rivers of Sumatra

1°23′44″N 100°56′04″E / 1.39555°N 100.93458°E / 1.39555; 100.93458