Brazil's southernmost state, Rio Grande do Sul, went on alert on Thursday (27) as the state Civil Defense monitoring center and the National Meteorology Institute (Inmet) warned of a stretch of storms expected to last through Monday (31). Rainfall totals may top 250 millimeters in the Vales, Serra and Nordeste regions between Friday and Monday, with a risk of flooding in the lowlands of the Taquari river basin downstream from the town of Encantado and of the Caí river from São Sebastião do Caí, according to G1.
The unstable weather began on Thursday with heavy rain and hail mainly in the state's southern region. On Friday (28), storms spread across the Costa Doce, the central region, the Porto Alegre metropolitan area and the middle coast, with up to 150 millimeters in 24 hours. Over the weekend, the heaviest rain concentrates in the Vales, Serra and Nordeste regions, which also face severe storms and winds above 90 km/h. Gusts in parts of the state may reach 100 km/h.
Rivers under watch
The Civil Defense hydrological outlook points to floods with streams overflowing, flash floods and urban flooding. In the state's south and west, the Quaraí, Ibirapuitã, Santa Maria, Jaguarão and Camaquã rivers are expected to rise, along with the Grande and São Lourenço streams, the São Gonçalo canal and the Mirim and Patos lagoons. In the northern half, the Paranhana, Sinos, Gravataí, Maquiné, Três Forquilhas, Passo Fundo and Várzea rivers and Taquari tributaries are also forecast to swell. For now, river levels across the state range between attention and normal thresholds.
The alert mobilizes a state still recovering from the May 2024 floods, the worst in its history, when the Taquari Valley was among the hardest-hit areas. This time, protective structures rebuilt since then were activated before the rain even arrived: GaúchaZH reported the closure of an emergency dike near Porto Alegre's airport and said President Lula canceled an event in the state because of the weather. On the state Civil Defense website, two orange alerts for storms with hail and wind in the southern region were active on Thursday. Inmet also issued danger and potential danger notices forecasting up to 100 millimeters of rain per day and a risk of power cuts in the southwest, the center and the metropolitan region.
Authorities advise residents not to shelter under trees during wind gusts, not to park vehicles near transmission towers or billboards and, when possible, to unplug electrical appliances. Civil Defense can be reached at 199 and the Fire Department at 193.