Flooding in Porto Alegre, Brazil

Flooding in Porto Alegre, Brazil
Flooding in Porto Alegre, Brazil

A winter storm brought torrential rain to southern Brazil, triggering deadly flooding in June 2023. The flooding reportedly killed more than a dozen people and left thousands without power in the country’s southern state of Rio Grande do Sul.

The storm slammed several communities near Porto Alegre, the state’s capital, with heavy rain and wind on June 16. In Maquiné, a municipality near the coast and one of the hardest hit areas, about 12 inches (300 millimeters) of rain accumulated in 24 hours, according to the state government. In São Leopoldo, just to the north of Porto Alegre, about 10 inches (250 mm) fell.

The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite acquired these natural-color images before and after the storm (left and right, respectively). The right image shows the affected area on June 19, 2023, three days after the storm. Sediment-rich water overtopped the banks of the Rio dos Sinos, inundating large stretches of farmland. Mud-stained runoff can be seen flowing into the Patos Lagoon, south of Porto Alegre.

The storm was an extratropical cyclone—a low-pressure system with cold air at its core. This cyclone brought some early winter snow to the Geral Mountains near Soledad (not in this view).

This is at least the third storm to cause major flooding in southern Brazil so far this year. In April 2023, strong wind, hail, and heavy rain damaged homes on the western side of Porto Alegre. And in March 2023, flooding contributed to major landslides and loss of life in São Paulo.

NASA Earth Observatory images by Lauren Dauphin, using MODIS data from NASA EOSDIS LANCE and GIBS/Worldview. Story by Emily Cassidy.

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