Niamey - Geography and Climate

Geography and Climate

Covering an area of over 250 km² the metropolitan area sits atop two plateaus reaching 218 m in altitude, bisected by the Niger River. At Niamey, the river, running almost straight SSE from Gao, makes a series of wide bends. The city was founded on the east ("left bank") of the river as it meanders from a west to east flow to run almost directly south. A series of marshy islands begin at Niamey and extend south in the river.

The climate is hot semi-arid (Köppen climate classification BSh), with an expected rainfall of between 500 mm (20 in) and 750 mm (30 in) a year, mostly beginning with a few storms in May, then accelerating to a rainy season usually lasting from sometime in June to early September, when the rains taper off rather quickly. Most of the rainfall is from late June to mid August. There is practically no rain from mid-October to April. Niamey is remarkably hot throughout the year. Average monthly high temperatures reach 38°C (100°F) four months out of the year and in no month does average high temperatures fall below 32°C (90°F). During the dry season, particularly from November through February, nights are generally cool. Average nighttime lows between November and February range from 14°C-18°C (57°F-64°F).