Senegal is favoured by a warm climate. The dry season runs from December through to May with cool trade winds in coastal areas. Throughout the rest of the year, a hot monsoon wind blows from the south bringing the rainy season and hot, humid weather. Rainfall is heaviest in Casamance and in the southeast and slight in the Sahelian region in the north and northeast, where temperatures tend to be higher.

Senegal is bordered by Guinea Republic and Guinea-Bissau to the south, Mali to the east and Mauritania to the north, and encloses the confederated state of The Gambia. To the west lies the Atlantic Ocean. Most land is less than 100m (330ft) above sea level, except for the Fouta Djallon foothills in the southeast and the Bambouk Mountains on the Mali border. On the coast between Dakar and St Louis is a strip of shifting dunes. South of Dakar there are shallow estuaries along the coastline, which is fringed by palm trees. In the northern part of the country, south of the Senegal Basin, lies the arid Fouta Ferlo, a hot dry Sahelian plain with little vegetation.