Tropical Storm Ernesto sloshed rather than slammed ashore — surprising forecasters by failing to strengthen Tuesday as it approached Florida and providing relief to hurricane-weary residents.

Briefly a hurricane Sunday, Ernesto lost much of its punch crossing mountainous eastern Cuba. The storm crossed the Florida Straits with top sustained winds of 45 mph before making landfall as a weak tropical storm at 11:30 p.m. on Plantation Key, about 60 miles southwest of Miami, forecasters said.

"Fortunately it didn't get too big," said David Rudduck of the American Red Cross. "It was the little train that couldn't."

• Check the National Hurricane Center's forecast to monitor Tropical Storm Ernesto.

That was good news for Florida, the victim of seven hurricanes since 2004.

"Frankly, I am surprised it has not strengthened," said Max Mayfield, director of the National Hurricane Center. "But for all those thousands and thousands of people with blue-tarped roofs, that's good news. ... As a homeowner, I'm very happy. As a forecaster, I'm not very happy."

As the threat of damaging winds abated, rain became the biggest concern, and police distributed thousands of sandbags in the low-lying Miami suburb of Sweetwater. Five to 10 inches of rain was possible, forecasters said.

Accidents on rain-slickened expressways killed at least two people. A Miami woman died after the car in which she was riding hydroplaned and struck a palm tree, and a motorcyclist was killed near Boca Raton after skidding and being struck by two other vehicles.

Still, officials had feared much worse weather. In the Keys, Monroe County emergency management director Irene Toner smiled as she watched steady rain fall.

"This is great," she said. "Compared to what it could have been, we are fortunate."

On Miami Beach, usually vibrant Lincoln Road was quiet, and many businesses closed early. Among those finding food at an Italian restaurant was actor Mickey Rourke with his dog Loki, wearing a pink argyle sweater.

"What storm?" Rourke said. "This is nothing."

The state had been ready to respond with 500 National Guard members and another 500 state law enforcement officers.

"This does not look like a catastrophic event, but we always want to be ready," Homeland Security Secretary Michael Chertoff said in Tallahassee. He attended Katrina anniversary events earlier in the day in Louisiana and Mississippi.

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Ernesto was forecast to move up the middle of the state and exit on the northeast coast by early Thursday, moving into the Atlantic and potentially gaining hurricane strength before hitting Georgia or the Carolinas.

NASA scrubbed Tuesday's launch of Atlantis. The space agency began moving the shuttle back to its hangar to protect it from the storm, then reversed course later in the day when forecasters predicted that winds would not be as severe as initially feared.

"It is always difficult to forecast intensity," Mayfield said. "We've been very honest with people about that."

Tropical storm watches or warnings remained in effect for much of coastal Florida. A hurricane watch was posted for the coasts of Georgia and the Carolinas.

At 11 p.m. EDT, Ernesto was hovering just off Plantation Key, centered over warm open water in the Florida Straits, about 65 miles south-southwest of Miami. It was moving north-northwest at 8 mph.

Across populous south Florida, residents scurried to make last-minute preparations before hunkering down. Lines formed early in the morning at groceries, gas stations, pharmacies and home supply stores, and many schools were closed through Wednesday.

The storm was especially worrisome for thousands of residents still awaiting repairs to damage from hurricanes in 2004 and 2005.

More than a thousand people sought refuge at shelters in Broward and Miami-Dade counties. Others embraced the weather as an opportunity. A squall preceding the storm brought out kite-surfers on Miami Beach until the wind became too strong.

In the laid-back Florida Keys, many residents took the storm in stride. At the Hurricane Grille in Marathon, wall-mounted televisions showed Ernesto heading for the Keys as Dean Carrigan enjoyed beer and a game of darts.

"It's definitely the Keys lifestyle that we're out here drinking and having a good time," he said.

Ernesto killed at least two people in Haiti, including a woman washed out to sea Sunday from a southern island, the country's civil protection agency said.

There were no reports of damage or deaths in Cuba. In an unusual public acknowledgment of the cooperation that has long existed between U.S. and Cuban weather services, the hurricane center thanked Cuba's government for permitting reconnaissance aircraft "to fly right up to their coastline to gather this critical weather data."

Meanwhile, off Mexico's west coast, Hurricane John grew into a powerful Category 3 storm, with maximum sustained winds of 115 mph. The storm threatened to cause flooding and ruin vacations in some Pacific resorts, but it was not expected to directly hit land.

John became the sixth Pacific hurricane of the season earlier in the day.

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