Over central Brazil rainfall is more seasonal, characteristic of a savanna climate. This region is as extensive as the Amazon basin but has a very different climate as it lies farther south at a higher altitude. In the interior northeast, seasonal rainfall is even more extreme. The semiarid climatic region generally receives less than 800 millimetres of rain, most of which generally falls in a period of three to five months of the year and occasionally less than this, creating long periods of drought.