Severe Cyclone to Hit Southern Brazil with Winds up to 120 km/h and Heavy Rainfall
An extratropical cyclone is set to cause extreme weather across Southern Brazil with heavy rain, strong winds, and public warnings from meteorological authorities.
- • Extratropical cyclone forming over southern Paraguay will impact southern Brazil from December 8 to 11.
- • Winds expected to reach 90-120 km/h, especially along the coast and highlands of Rio Grande do Sul and Santa Catarina.
- • Inmet issued a high-danger storm warning with heavy rain, hail, and risks of flooding and damage.
- • Safety instructions include disconnecting electrical devices and seeking shelter; emergency services are on alert.
Key details
Southern Brazil is bracing for a powerful extratropical cyclone expected to bring heavy rains, strong winds, and hazardous conditions between December 8 and 11, 2025. According to meteorological reports, the cyclone will develop over southern Paraguay and northeastern Argentina before reaching Rio Grande do Sul early Tuesday.
As the cyclone intensifies, it will cause wind gusts ranging from 90 to 120 km/h, particularly impacting coastal and elevated regions of Rio Grande do Sul and Santa Catarina between Wednesday and Thursday. The system’s atmospheric pressure will fall below 1000 hPa, generating severe thunderstorms and storms with potential hail, heavy rainfall exceeding 60 millimeters per hour (or more than 100 millimeters per day), and widespread disruptions.
The National Institute of Meteorology (Inmet) has issued a high-danger storm warning for Southern Brazil, valid from midday Monday to late Tuesday, covering parts of Santa Catarina, Rio Grande do Sul, and Paraná. Inmet’s forecast highlights considerable risks including building damage, power outages, crop destruction, fallen trees, flooding, and transportation interruptions. Metropolitan areas such as Porto Alegre and Curitiba are among those expected to experience the most severe conditions.
It is advised that residents follow safety measures such as disconnecting electrical devices, protecting important documents, and seeking shelter when necessary. Emergency services like Civil Defense and the Fire Department are on alert to provide assistance.
While the cyclone’s effects will also be felt in the Southeast and Midwest states, including São Paulo, Rio de Janeiro, Minas Gerais, and Mato Grosso do Sul, the most critical impacts will occur in the South. The cyclone will reach the coast of Rio Grande do Sul by Wednesday morning before moving offshore on Thursday. Porto Alegre faces heightened risk from early Tuesday with conditions peaking midweek.
Officials caution that this is a significant weather event with potential for extensive disruption and encourage constant monitoring of updates.
This article was synthesized and translated from native language sources to provide English-speaking readers with local perspectives.