Two tropical storms advanced across the Caribbean Saturday as potentially historic threats to the U.S. Gulf Coast, one dumping rain on Puerto Rico and the Virgin Islands while the other was pushing through the gap between Mexico's Yucatan Peninsula and Cuba.

Tropical Storms Laura and Marco were both projected to approach the U.S. Gulf Coast at or close to hurricane force. The current, uncertain track would take them to Texas or Louisiana.

Two hurricanes have never appeared in the Gulf of Mexico at the same time, according to records going back to at least 1900, said Colorado State University hurricane researcher Phil Klotzbach. The last time two tropical storms were in the Gulf together was in 1959, he said.

The last time two storms made landfall in the United States within 24 hours of each other was in 1933, Klotzbach said.

The projected track from the U.S. National Hurricane Center would put both storms together in the Gulf on Tuesday, with Marco hitting Texas and Laura making landfall a little less than a day later, though both tracks remain uncertain.

Laura was already flinging rain across Puerto Rico and the Virgin Islands Saturday morning and was expected to drench the Dominican Republic, Haiti and parts of Cuba during the day on its westward course.

Puerto Rico Gov. Wanda Vázquez declared a state of emergency and warned that flooding could be worse than what Tropical Storm Isaias unleashed three weeks ago because the ground is now saturated.

“No one should be out on the streets,” she said.

The storm was centered about 20 miles (30) kilometers south of San Juan, with maximum sustained winds of 40 mph (65 kph). It was moving west at 18 mph (65 kph). Officials said they were most concerned about the thousands of people who still have been living under blue tarps since 2017's Hurricane Maria and the hundreds of families living along Puerto Rico's southern coast in homes damaged by a string of strong earthquakes this year.

Marco, meanwhile, was strengthening while centered about 105 miles (170 kilometers east of Cozumel island, headed to the north-northwest at 12 mph (19 kph). It had maximum sustained winds of 65 mph (100 kph). It was expected to become a hurricane later in the day.

The Hurricane Center said it expects the storms to stay far enough apart to prevent direct interaction as the region braces for the peak of the Atlantic hurricane season, which is forecast to be unusually active.

Both storms were expected to bring 3 to 6 inches (8 to 15 centimeters) of rain to areas they were passing over or near, threatening widespread flooding across a vast region.

“A lot of people are going to be impacted by rainfall and storm surge in the Gulf of Mexico,” said Joel Cline, the tropical program coordinator for the National Weather Service. “Since you simply don’t know, you really need to make precautions.”

It seems fitting for such an unusual twin threat to arrive in 2020, said University of Miami hurricane researcher Brian McNoldy.

“Of course, we have to have two simultaneously land-falling hurricanes,” McNoldy said. “It’s best not to ask what’s next.” )

Forecasters said that while atmospheric conditions are favorable for Laura to grow, its passage over Puerto Rico and the mountains of Haiti, the Dominican Republic and Cuba that could tear it apart or weaken it before it enters warm Gulf waters conducive to growth.

Officials in the Florida Keys, which Laura might pass over on its route into the Gulf, declared a local state of emergency Friday and issued a mandatory evacuation order for anyone living on boats, in mobile homes and in campers. Tourists staying in hotels should be aware of hazardous weather conditions and consider altering their plans starting on Sunday, Monroe County officials said in a news release.

 

Citing both storm systems, Louisiana Gov. John Bel Edwards declared a state of emergency Friday night. “It is too soon to know exactly where, when or how these dual storms will affect Louisiana, but now is the time for our people to prepare for these storms,” Edwards said in a statement.

Laura had earlier forced the closure of schools and government offices in the eastern Caribbean islands of Anguilla and Antigua, according to the Caribbean Disaster Emergency Management Agency.

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