Torrential rain and cyclone-induced winds have resulted in a tragic loss of life in southern Brazil, claiming the lives of at least 21 individuals, and there is a looming threat of further flooding.

The governor of Rio Grande do Sul has characterized this calamity as the most severe weather disaster the state has ever witnessed. Thousands of residents have been compelled to evacuate their homes, according to official reports.

In the town of Mucum, home to 5,000 residents, local media has reported that hundreds had to be rescued from their rooftops due to the inundation, which submerged approximately 85% of the town.

President Luiz Inácio Lula da Silva pledged that the federal government stands prepared to provide assistance, stating, "Whenever there is a crisis, the federal government will be there to aid those affected by these hardships."

During a press conference, Eduardo Leite, the governor of Rio Grande do Sul, announced the discovery of 15 more bodies in Mucum on Tuesday, bringing the total death toll to 21.

Authorities have reported that the state experienced over 300 mm (11 inches) of rainfall in under 24 hours, leading to widespread flooding and landslides.

"There are still people missing," Mucum Mayor Mateus Trojan told Radio Gaucha.

"The death toll might climb higher. The town of Mucum as we knew it no longer exists."

Rescue workers have been using helicopters to reach areas cut off by flooding.

Further north in Nova Bassano, resident Dirce Reginatto said she was "devastated".

"There are many people who lost much more, but here at home I have nothing left," she told the Reuters news agency.

Luana Da Luz, from Passo Fundo, was rescued by firefighters.

"We saw it [water] was going to fill everything since dawn," she said. "We were already putting things on top of the table and the wood stove, but it didn't help."

Many factors contribute to flooding, but a warming atmosphere caused by climate change makes extreme rainfall more likely.

The world has already warmed by about 1.2C since the industrial era began and temperatures will keep rising unless governments worldwide make steep cuts to emissions.

In February, at least 40 people were killed in flooding and landslides in Brazil's São Paulo state. while last year at least 100 people died as torrential rain triggered landslides and torrents of mud near the city of Recife in the country's north-east.

What a tragedy, flood hits Brazil again

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