Two main seasons, one wet and one dry, divide the climatic year. The wet season, from November through March, has monthly averages between 27°C and 29°C (81–84°F), with cooler temperatures in the interior uplands. The dry season lasts from April to October and has June and July temperatures averaging 18–20°C (64–68°F). The average annual rainfall is greatest (about 142 cm/56 in) over the western hills and the central areas, and lowest (30 cm/12 in) in the southwest.