2023 South America heat wave

Between July and September 2023, a heat wave hit South America, leading to temperatures in many areas above 95 F in midwinter, often 40–45 F-change 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. Several states also had the hottest September temperatures in history, often reaching more than 40°C.

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, which was also exacerbated by El Niño and global warming.

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".

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.