Gustav weakens to tropical storm

(CNN) -- Hurricane Gustav weakened to a tropical storm as it aimed for Caribbean waters Tuesday evening after crossing onto Haiti's southern peninsula as a Category 1 storm that killed at least one person.

At 11 p.m. EDT, Gustav had maximum sustained winds of 70 mph.

Earlier, Gustav triggered a landslide near the Haitian town of Brazillienne that killed a man, according to Pinchinat Pierre Louis, deputy director of civil protection in Haiti.

Pierre Louis also said floodwaters had split the southern town of Jacmel in half.

Forecasters expect the storm to move off Haiti and into the Windward Passage later Tuesday and then slowly sweep across or near Cuba's southeastern coast before moving into the open waters of the Gulf of Mexico.

Once it is over the Gulf's warm water, which might not happen until Saturday, Gustav could become a "major hurricane," at least Category 3 status with sustained wind speeds of 111 mph (96 km/h) or more, forecasters said.

Carrying winds of up to 90 mph (145 km/h), the storm made landfall Tuesday afternoon about 10 miles (16 km) west of the southern town of Jacmel, Haiti, the Miami, Florida-based National Hurricane Center said.

As of 11 p.m. ET, Gustav's maximum winds were holding at near 70 mph (110 km/h) with some higher gusts, the hurricane center said.

The storm's center was about about 85 miles (135 km) west of Port-au-Prince, Haiti, and about 150 miles (245 km) southeast of Guantanamo, Cuba.

Gustav's forward speed had slowed to 7 mph (11 km/h), the hurricane center said. The storm was expected to slow and turn toward west-northwest later Tuesday and move generally in that direction Wednesday.

"Hurricane Gustav should pass near the southwestern peninsula of Haiti tonight and move near or just south of eastern Cuba on Wednesday," the hurricane center said. Watch vehicles stranded in flooding in Santo Domingo »

In Baton Rouge, Louisiana, meanwhile, authorities warned residents to be prepared for another major storm.

"We all hope this will be a false alarm," Gov. Bobby Jindal said. "Now would be a good time, however, for families to review their evacuation plans."

Hurricane Katrina killed more than 1,800 people when it struck New Orleans on August 29, 2005, flattening towns on the Mississippi Gulf Coast and flooding more than three-quarters of the city.

Jindal said Louisiana is "better prepared than before," with hundreds of buses and tens of thousands of shelter beds lined up in preparation for another storm.

He said forecasts showing Gustav headed toward the Gulf Coast as a major hurricane were "extremely tentative" but urged Louisianans to gas up their cars, stock up on food and water to last three days and refill prescriptions in case evacuations become necessary.

As a precaution, Shell Oil Co. said, it was making arrangements to evacuate staff not essential to production or drilling from the Gulf of Mexico.

"Evacuations could begin as early as Wednesday," the company said.

However, hurricane movements are erratic, and long-range forecasts often miss. The hurricane center's "track forecast cone" estimates the center of the storm could be anywhere between Key West, Florida, and the eastern end of Mexico's Yucatan Peninsula by Saturday.

A hurricane warning, meaning sustained winds of at least 74 mph (119 km/h) are expected within a day, remained in effect for the Cuban provinces of Guantanamo, Santiago de Cuba and Granma.

The Dominican Republic discontinued the warning for the eastern part of Hispaniola, the island it shares with Haiti. iReport.com: See images of flooding in Dominican Republic

Hurricane watches -- meaning hurricane conditions are possible within the watch area in 36 hours -- were in effect for the Cayman Islands, Haiti from Le Mole St. Nicholas to the northern Haiti-Dominican Republic border, the Cuban provinces of Las Tunas and Holguin and Jamaica. iReport.com: Send us your photos, stories

The storm was expected to dump about 4 to 8 inches of rain over Hispaniola, eastern Cuba and Jamaica, with some areas getting up to 20 inches.

"These rains will likely produce life-threatening flash floods and mud slides," the hurricane center said. "Coastal storm surge flooding of 2 to 4 feet above normal tide levels along with large and dangerous battering waves can be expected in areas of onshore winds in the hurricane warning area."

Gustav prompted several flight cancellations on Tuesday, most to Haiti, airport spokesmen said. An American Airlines flight from Fort Lauderdale International Airport in Florida to Port-au-Prince, Haiti, and another going the opposite direction were canceled, Fort Lauderdale airport spokesman Greg Meyer said.

Miami International Airport spokesman Greg Chin said six additional flights there had been canceled: four to and from Haiti and two between Miami and Belize.

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