The former hurricane known as Eta was expected to regain strength Friday as it aimed its torrential rain and strong winds at South Florida and the Florida Keys, federal forecasters said.
Eta, which was downgraded to a tropical storm and then to a tropical depression Wednesday, caused a massive landslide Friday in San Cristobal Verapaz, Guatemala, where 100 people may have died, President Alejandro Giammattei said.
Video from Guatemala shows an army helicopter being used to rescue a family from a rooftop as flood waters inundated their community.
The storm Friday was about 115 miles east of Belize City, Belize, and was moving northeast at 7 mph, according to the National Hurricane Center. It had maximum sustained winds of 35 mph as the Cayman Islands and parts of Cuba were under tropical storm warnings.
Moving across the northwestern Caribbean on Friday, Eta was expected to restrengthen to a tropical storm. It was forecast to spread heavy rain from Central America to southeastern Mexico and from Jamaica to the Cayman Islands.
Parts of South Florida and the Florida Keys were in for the possibility of 15 inches of rain by the time Eta brushes the coastline and then heads into the Gulf of Mexico on Monday, the center said.
Winds by then could reach 65 mph, too weak to be considered hurricane-force, said atmospheric research scientist Phil Klotzbach of Colorado State University.
The big concern as Eta aims for the U.S. is precipitation and the possibility of flash flooding, forecasters said.
"This is going to be a very big and very serious rain event," said National Hurricane Center meteorologist and spokesman Dennis Feltgen. "There's a serious threat of some urban flooding."
He urged Florida residents to pay attention to the forecast.
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Eta is considered life-threatening in part because it's spending plenty of time in one place. "The storm is forecast to move relatively slowly as it approaches" the U.S., Klotzbach said by email.
U.S. landfall was yet to be forecast. Eta was expected to weaken after it enters the Gulf of Mexico, Feltgen said.
Eta is punctuating a record-setting year in which 11 named tropical cyclones have made landfall in the continental United States.