Extratropical Cyclone Strikes Brazil’s South as Rio Swelters and São Paulo Faces Storm Risk

Overview

• National weather alerts report heavy rain of up to 100 mm per day and gusts near 100 km/h across Santa Catarina, Paraná and Rio Grande do Sul with the year’s first extratropical cyclone.
• São Paulo is under a statewide alert for isolated severe storms along the eastern corridor, with the capital seeing late‑day showers, treefall calls and wind gusts up to 70 km/h on Saturday.
• Rio de Janeiro is at level 3 of the municipal Heat Protocol with temperatures near 39–41°C, and the Alerta Rio system warned of very low relative humidity between 21% and 30%.
• Health and civil‑defense measures include hydration points at 27 state UPAs and Cedae’s distribution of 10,000 liters of chilled water along the waterfront, alongside guidance to limit sun exposure and stay hydrated.
• Inmet and local services forecast expanding convective storms from Monday across the center‑south, likely easing temperatures by midweek, though Rio may still touch 40–41°C on Monday with isolated showers.