The climate is tropical in the south, monsoonal in the north with hot rainy season from mid-May to mid-September and warm, dry season from mid-October to mid-March. There is occasional typhoons with extensive flooding.
The terrain is consists mostly of low, flat delta in the south and north with central highlands, hilly mountainous in the far north and north-west. Natural resources include phosphates, coal, manganese, bauxite, chromate, offshore oil deposits and forests.