Continuing the intense heat wave, São Paulo hit 36.9°C on Sunday (Dec 28)—eclipsing the Dec 26 record and the hottest of 2025—while Pedro de Toledo reached 42.1°C. With health risks rising and reservoirs strained, Inmet's red alert persists until Dec 29, but storms loom starting Monday.
São Paulo's heat wave intensified on December 28, 2025, with the Inmet station at Mirante de Santana recording 36.9°C around 4 p.m., topping the previous December record of 35.6°C (Dec 3, 1961) and the Dec 26 high of 36.2°C. Automatic readings hit 37.2°C, the fourth straight day above 35°C.
Statewide, Civil Defense noted Pedro de Toledo (42.1°C), Miracatu (41.6°C), and Itaóca (40°C) as hottest spots. Inmet's red alert for extreme heat—temperatures 5°C above average—covers 1,284 municipalities including the capital through Dec 29, warning of health dangers after prolonged exposure.
Health impacts mounted: State Health Secretariat data showed a 27% rise in sunstroke-related outpatient visits (1,052 cases Jan-Oct 2025 vs. 827 in 2024), though hospitalizations fell to 2. Elderly and children remain most vulnerable to dehydration and hyperthermia.
A shift is forecast: CGE predicts rain, gusts over 50 km/h, lightning, and hail from evening Dec 28 into Monday (29), with isolated showers already in northern zones and Guarulhos. Tuesday (30) brings highs near 29°C and heavier rain risks like flooding and outages. "Hot, humid air and sea breezes will spark moderate to heavy rain," CGE noted. Advice: hydrate, avoid midday sun, never leave vulnerable people in cars.
