Brazil Braces for Third Heat Wave as South Faces Severe Storms

Overview

• Forecasters said Monday that Brazil is in a third 2026 heat wave from Aug. 15–20 with daytime highs possibly reaching about 42°C in Mato Grosso do Sul, Mato Grosso, Goiás and Tocantins.
• The Instituto Nacional de Meteorologia (Inmet) has issued widespread low‑humidity alerts, including 'perigo' and 'perigo potencial' levels, warning relative humidity near 20% in many interior areas and advising hydration and reduced outdoor exertion.
• The South is under a contrasting hazard profile with a red storm alert in parts of Rio Grande do Sul for heavy rain, flooding and landslides and reported hail events that affected 92 people in the state.
• Local authorities report concrete disruptions: ferry and maritime services suspended in Bahia, gusts forecast to 46 km/h in Sergipe, and scattered infrastructure damage and at least one rain‑related death in Santa Catarina.
• Models and bulletins show a polar air mass and a frontal system are forecast to advance between Aug. 20 and 22, which should erode the heat and bring cooler, windier conditions and renewed storm risk in the south.