Two tornadoes confirmed in Paraná, extratropical cyclone forecast to form near southern Brazil

Paraná Environmental Technology and Monitoring System (Simepar) confirmed the first tornado near Francisco Alves at about 17:00 LT on September 9. The tornado was short-lived and affected a small, localized area. Simepar said no damage had been directly associated with its passage at the time of its assessment, preventing an intensity classification.

The tornado developed from a supercell that also produced heavy hail and damage elsewhere in Francisco Alves. A second tornado was confirmed at about 00:40 LT on September 10 in Espigão Alto do Iguaçu. Simepar said damage assessment was underway and that the tornado’s intensity would be determined after evaluating the damage using Fujita-scale criteria.

A landslide struck a residence in the Ronda neighborhood of Ponta Grossa during heavy rain on the morning of September 10, killing a 21-year-old couple and their 5-year-old child. Firefighters were called at about 08:44 LT and found the three victims buried by soil, mud, and debris inside a bedroom. Ten firefighters and five vehicles responded, with support from SAMU, the Municipal Guard, Military Police and Civil Defense. The surrounding area was restricted because of the risk of additional slope failures.

A report from Paraná’s Civil Defense Information System (SISDC) showed 583 people affected across 11 municipalities, although the tally had not yet included the fatal landslide in Ponta Grossa. Espigão Alto do Iguaçu accounted for 500 affected people, while impacts were also recorded in municipalities including Marechal Cândido Rondon and Manfrinópolis.

About 22 900 customer units were without electricity across Paraná, according to Copel figures reported by Brazilian media on September 10. CBN Curitiba reported 7 500 outages in the Curitiba metropolitan region and coast, 5 900 in western Paraná, 3 700 in the northwest, 3 000 in the southwest, 1 800 in the center-south and 832 in the north. Copel said restoration crews were working on the network and that the number of interruptions was expected to decline as repairs progressed.

INMET said atmospheric instability is expected to intensify on Friday, September 11 as an extratropical cyclone forms during the night between northeastern Rio Grande do Sul and the Atlantic Ocean. The cyclone is forecast to move rapidly toward the ocean on September 12, when INMET expects it to reach maximum intensity.

INMET placed central, western and southern Paraná and Santa Catarina, along with northern and northwestern Rio Grande do Sul, under red warnings for dangerous thunderstorms on September 11. The agency forecast heavy rain, damaging wind gusts and hail, with the possibility of tornadoes, particularly across central-southern and western Paraná and Santa Catarina and northwestern Rio Grande do Sul.

INMET’s forecast calls for surface gusts above 70 km/h (43 mph) across parts of Mato Grosso do Sul, Paraná and São Paulo, while accumulated rainfall from September 10 through the end of September 12 could exceed 150 mm (5.9 inches) in parts of southern and southeastern Brazil. During September 12, the strongest cyclone-related wind gusts are forecast to become increasingly concentrated over the Atlantic near the southern and southeastern coast, before the system gradually moves away and weakens.

References:

¹ Simepar confirma dois tornados no Paraná entre quarta (09) e quinta-feira (10/09) – Simepar – September 10, 2026

² Previsão para sexta-feira (11) e sábado (12): Formação de um ciclone extratropical na costa da Região Sul do Brasil intensifica as instabilidades no Sul e em partes do Centro-Oeste e do Sudeste – INMET – September 10, 2026

³ Família morre após barranco desabar em cima de casa durante temporal no PR – UOL – September 10, 2026