Brazil braces for first El Niño‑driven storm surge in the south

A wave of severe thunderstorms is forecast to hit southern Brazil and neighboring Uruguay, Argentina and Paraguay from Thursday, 16 Oct, through at least Tuesday, 21 Oct. MetSul Meteorology expects intense rain rates of 100‑200 mm, with some locations possibly receiving 200‑300 mm, raising the risk of supercell storms, large hail, strong wind gusts, tornado‑like micro‑explosions and rapid river rises that could cause flash floods and landslides.

Cemaden’s operations chief Marcelo Seluchi noted that El Niño years historically bring concentrated heavy rains, and the monitoring network has been expanded and restored after 2024 damage. An unusually warm air mass, combined with a low‑level jet originating over Bolivia and central Brazil, will feed the instability, producing prolonged wind bursts and further enhancing the storm potential across the Southern Cone.

Authorities are issuing alerts and urging communities to stay vigilant as the atmospheric conditions could lead to sudden inundations and wind‑related damage throughout the region.