🇬🇲Gambia

Spanning 13°00′–13°50′N, The Gambia is the smallest continental African country at approximately 11,300 km², a thin sliver of land 50 km wide at most stretching far inland along the lower Gambia River, fully enclosed by Senegal except at its short Atlantic coast. The terrain is entirely low-lying and rarely exceeds 50 m elevation, with the river itself navigable far inland.

The climate is uniformly tropical savanna Aw modulated by Atlantic sea-surface temperatures near the coast at Banjul, becoming hotter and more continental approaching the eastern border. The West African monsoon delivers a strongly seasonal single rainfall regime, with the cool dry Harmattan winds from the Sahara dominating the winter dry season.

Banjul sees highs of 33°C and nights of 18°C in January and highs of 32°C and nights of 24°C in August with 900–1,100 mm of rainfall almost entirely concentrated between July and September, followed by a long bone-dry season from November to May. Basse Santa Su in the far east is significantly hotter, with daytime highs of 32–41°C through the year and approximately 900 mm, showing stronger Harmattan dust-haze influence. Relative humidity climbs to 80–90% during the wet season and drops below 50% in the Harmattan months.

Major climate hazards include severe Sahel droughts (notably 1972–73 and 1982–84) that damaged peanut and rice agriculture, intensifying coastal erosion threatening Banjul, and recurrent severe wet-season flooding, with the 2022 flash floods affecting thousands.

Comparing the last decade against the 1940–1970 baseline, mean temperatures across these cities have risen by about 0.9°C.