The hydrographic network in Portugal has a north-south contrast, with rivers in the north having higher flows due to greater rainfall. Portuguese rivers generally flow from northeast to southwest towards the Atlantic. The rivers are characterized by irregular flows associated with an irregular climate, causing floods in winter when rainfall is heavy and drying in summer. Over 80% of mainland Portugal experienced severe drought in September 2017 according to the IPMA, with rainfall 70% below normal and temperatures far above average, resulting in high evapotranspiration and low soil moisture levels across much of the interior and south. The drought conditions led the government to provide exceptional support to farmers for water access.