 An exception to this is the northern tropical regions.The Kimberley has an extremely hot monsoonal climate with average annual rainfall ranging from , but there is a very long dry season of 7 months from April to November.Eighty-five per cent of the state's runoff occurs in the Kimberley, but because it occurs in violent floods and because of the insurmountable poverty of the generally shallow soils, development has only taken place along the Ord River.