Two main seasons, one wet and one dry, divide the climatic year. The wet season, from November through March, has monthly averages 27–29°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.