Watch: Massive tsunami-like cloud approaches a beach in Brazil
The ominous-looking cloud stunned beachgoers in São Paulo, Brazil, as it approached the South American beach.
Strange-looking cloud approaches a beach in Brazil
A massive roll cloud stunned beachgoers as it loomed off the coast of São Paulo, Brazil. According to the FOX Forecast Center, a roll cloud is a low, horizontal, tube-shaped cloud associated with a thunderstorm gust front.
An ominous-looking cloud stunned beachgoers in São Paulo, Brazil, on Saturday as it approached the South American beach.
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Footage captured by Gabriel Ferraz de Campos Naufel showed the unusual, tsunami-like cloud expanding across the sky.
"I was at Bonete Beach in Ilhabela, São Paulo, on my boat, when I saw a strange, cylindrical-shaped cloud approaching; it also seemed to have tentacles," Naufel told local news agencies.

A satellite view of where the roll cloud occurred.
(FOX Weather / FOX Weather)
In other videos posted during the phenomenon, people appeared mesmerized by the event.
According to the FOX Forecast Center, the ominous-looking cloud was a phenomenon called a roll cloud, which is a low, horizontal, tube-shaped cloud associated with a thunderstorm.

A roll cloud advances over a beach.
(MARIANA SUAREZ/AFP via Getty Images / Getty Images)
During a roll cloud event, the cloud becomes completely detached from the thunderstorm base and typically appears to roll horizontally across the sky.
The FOX Forecast Center says the roll cloud in São Paulo formed at the end of a thunderstorm, which sent a burst of cool air outward along the surface.

A satellite view on how the roll cloud occurred in Brazil.
(FOX Weather / FOX Weather)
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As the cooler air advanced, warmer, humid air was forced upward.
These conditions ultimately created the tsunami-like roll cloud seen over the beach.
