Between July and September 2023, a heat wave hit South America, leading to temperatures in many areas above 95 °F (35 °C) in midwinter, often 40–45 °F (22–25 °C) degrees above typical. The heat wave was especially severe in northern Argentina and Chile, along neighboring areas in and around the Andes Mountains. Some locations set all-time heat records.[1] Several states also had the hottest September temperatures in history, often reaching more than 40°C.[2]
In mid-July, Brazil began experiencing elevated temperatures. During the third week of the month, locations in Argentina, Bolivia, Paraguay, and Uruguay set records for July temperatures. There was a heat dome above Paraguay associated with the unusual weather,[1] which was also exacerbated by El Niño and global warming.[3]
Weather historian Maximiliano Herrera stated that "South America is living one of the extreme events the world has ever seen" and "This event is rewriting all climatic books".[1]
On 12 August 2023, Buenos Aires broke a 117 year heat record. Chile saw highs towards 40 °C and Bolivia saw unseasonably high temperatures, while Asunción saw 33 °C.[4]