Record flooding over the past month has killed 163 people and displaced 600,000 more. Another 64 people are still missing.
Rains had lightened to a drizzle over the past few days, with stores beginning to open and residents working to rebuild.
But the skies opened on Thursday morning, dumping heavy rains and flooding areas of Porto Alegre all over again.
One day care in the neighborhood of Menino Deus, which reopened Wednesday after a weeklong cleanup, was forced to evacuate as the rain rushed in.
“It all happened very quickly, [the flooding happened] much faster than last time,” said the director of the child care center, who did not give her name.
In a span of 12 hours, parts of Porto Alegre received more rain than they typically do in a month, according to data from the national meteorological institute.
The flooding Thursday also hit areas of Porto Alegre, including the south, which had previously gone unscathed.
Gimena Samuel had to call for her elderly parents to be rescued in the neighborhood of Cavalhada, where streets were flooded and cars unable to get through.
“There are a lot of elderly people here who can’t get out by themselves,” she said.
Earlier this week, the city of Porto Alegre had asked residents to leave their trash out on the sidewalk to be thrown away. However, the fresh rain carried the trash out onto the street, clogging drains and worsening the flooding.
Porto Alegre Mayor Sebastiao Melo told reporters the city was not surprised by the downpour, but that it was “excessively heavy.”
Residents, however, complained about the lack of warning.