Dry season
The hydrographs of the District are largely constituted by streams and rivers which form a part of the basin of the Akagera River. The main rivers are the Akagera and the Nyabarongo, which flows through the city of Kigali from Lake Muhazi. The District has four seasons. Two rainy seasons and two dry seasons, alternating in the following manner: Small dry season: December, January and February Big rainy season March, April and May Big Dry season June, July, August and September Small rainy season October and November. These seasons are often irregular due to world climate changes. Lower or higher limits of each Season cannot be determined accurately. The rainy season may drag on into the dry season and vice versa. Average temperature is 22°C for a rainfall varying between 900 and 1150 mm of annual rain.