Updated

Haitians were told to prepare for evacuations as Tropical Storm Gustav formed quickly Monday in the Caribbean on a path to hit — as a hurricane — the country's denuded southern coast before moving on to Cuba, the Bahamas and Florida.

Haiti upgraded storm warnings to hurricane warnings along much of its coast Monday as Gustav closed in from the south.

By Monday afternoon, reports from an Air Force Hurricane Hunter aircraft indicated that top sustained winds had already reached nearly 60 mph as Gustav moved northwest, the U.S. National Hurricane Center in Miami said. Forecasters said Gustav's center could pass near or over Haiti on Tuesday.

Floods and landslides were possible across Haiti's southern peninsula, and the forecasts suggested the eye could pass very closely to the capital of Port-au-Prince, home to nearly 3 million people. Early Monday evening, the storm was centered about 180 miles southeast of Port-au-Prince.

Carnival Cruise Lines diverted one of its ships to a Mexican port instead of Montego Bay, Jamaica, to avoid the storm, company spokesman Vance Gulliksen said. Other cruise lines said they were closely tracking the storm's path.

The commander of the Guantanamo military base in Cuba, where the U.S. holds about 265 men, many suspected of belonging to al-Qaida or the Taliban, ordered U.S. military personnel to prepare for the storm to hit late Tuesday or early Wednesday.

"We're monitoring the track of ... Gustav and reviewing our destructive weather plans and procedures," said Army Maj. Richard Morehouse, a spokesman for detention operations at the base.

Vulnerable to high winds are dozens of tents pitched on an abandoned runway where those attending war-crimes trials for alleged terrorists are housed. No hearings are scheduled this week.

Morehouse told The Associated Press that the lockups housing all detainees "are capable of withstanding hurricane force winds and rain."

Haitians were told to stay on alert for evacuations and to avoid crossing flooded rivers, the cause of nearly all 23 deaths on the greater island of Hispaniola during last week's Tropical Storm Fay.

The agricultural ministry, already dealing with a food crisis and fighting to raise national production, advised farmers to put livestock in safe locations. All maritime activities also were suspended until further notice.

Few people in Haiti's capital appeared to be aware of the brewing storm as rumors spread of new protests against high food and education prices planned for this week. Haitian radio reported that a handful of protesters burned tires Monday in Les Cayes, a town in the southwest.

"I didn't know there was a tropical storm coming," said Dunis Amilca, a 29-year-old resident of the oceanside Port-au-Prince slum of Cite Soleil. "I'm just going to stay in my house and watch out for it."

Dominican authorities also issued storm warnings and advised small boats to remain in port, even on the north side of the island of 17 million people.

Meanwhile, two other tropical storms were lashing the southeastern U.S. and Mexico's Pacific coast.

The remnants of Fay brought heavy rain and winds from Georgia to Louisiana. Floridians were still mopping up floodwaters from a storm that stuck around for a week and made a historic four landfalls, dumping more than 30 inches of rain along the central Atlantic coast.

The National Weather Service said the vestiges of Fay would deluge northern Georgia on Monday and Tuesday with 3 inches to 5 inches of rain expected in the Atlanta area and up to 8 inches in northeast Georgia. In Alabama, flash flood and tornado warnings were posted.

In Mexico, Tropical Storm Julio dumped rain on the southern half of the Baja California peninsula Monday before heading toward the northern Gulf of California.

A tropical storm warning was issued for the peninsula's east coast from Loreto to Bahia de los Angeles, and for the mainland from Guaymas to Puerto Libertad.

But Julio caused little major damage and was expected to weaken to a depression by Tuesday. Forecasters said it would likely drench the U.S. Southwest in coming days.

The National Hurricane Center said Julio was located about 15 miles north-northwest of Santa Rosalia, Mexico, and heading north-northwest at 12 mph. It had top winds near 40 mph.

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