The landscape is characterized by mostly flat to rolling coastal plains that contain mangroves and swamps, which rise to a rolling plateau and low mountains in the northeast.

Tropical rainforests cover the hills, while elephant grass and semi-deciduous forests make up the dominant vegetation in the northern sections. The equatorial climate is hot year-round with heavy rainfall from May to October with a short interlude in mid-July to August.During the winter months of November to March, dry dust-laden harmattan winds blow inland, causing many problems for residents.

Liberia's watershed tends to move in a southwestern pattern towards the sea as new rains move down the forested plateau off the inland mountain range of Guinée Forestière, in Guinea. Cape Mount near the border with Sierra Leone receives the most precipitation in the nation.

Liberia's main northwestern boundary is traversed by the Mano River while its southeast limits are bounded by the Cavalla River. Liberia's three largest rivers are St. Paul exiting near Monrovia, the river St. John at Buchanan and the Cestos River, all of which flow into the Atlantic. The Cavalla is the longest river in the nation at 515 kilometres (320 mi).

The highest point wholly within Liberia is Mount Wuteve at 1,440 metres (4,724 ft) above sea level in the northwestern Liberia range of the West Africa Mountains and the Guinea Highlands.However, Mount Nimba near Yekepa, is higher at 1,752 metres (5,748 ft) above sea level but is not wholly within Liberia as Nimba shares a border with Guinea and Côte d'Ivoire (Ivory Coast) and is their tallest mountain as well.