Hurricane Sally lashes Florida, Alabama coasts with heavy rain, pounding surf

Heavy rain and pounding surf driven by Hurricane Sally hit the Florida and Alabama coasts Tuesday as forecasters expected the slow-moving storm to dump continuous deluges before and after landfall, possibly triggering dangerous, historic flooding along the northern Gulf Coast.

"It's going to be a huge rainmaker," Phil Klotzbach, a research scientist and meteorologist at Colorado State University. "It's not going to be pretty."

The National Hurricane Center (NHC) said Tuesday evening that winds were picking up and life-threatening flooding is likely along portions of the Gulf Coast as the slow-moving hurricane crawls just off the coast.

At 7 p.m. CT, the centre of the storm was located about 125 kilometres south of Mobile, Ala., and about the same distance southwest of Pensacola, Fla. The hurricane's top sustained winds have been clocked at 130 km/h. It's crawling northward at four km/h.

The NHC expects Sally to remain a Category 1 hurricane when it makes landfall late Tuesday or early Wednesday. 

The National Weather Service said ten centimetres of rain has already fallen in some areas, and a flash flood warning has been issued in some areas. Meanwhile, monitoring stations have recorded gusts above 96 km/h at Mobile and Pensacola.

By Tuesday evening, hurricane warnings stretched from east of Bay St. Louis, Miss., to Navarre, Fla. Rainfall of up to 50 centimetres was forecast near the coast. There was a chance the storm could also spawn tornadoes and dump isolated rain accumulations of 76 centimetres.

Heavy rain and surf pounded the barrier island of Navarre Beach on Tuesday afternoon and road signs wobbled in the gusty wind.

Rebecca Studstill was among those watching. Studstill, who lives inland, was wary of getting stuck on the island, saying police close bridges once the wind and water get too high. "Just hunkering down would probably be the best thing for folks out here," she said.

Two large casino boats broke loose Tuesday from a dock where they were undergoing construction work in Bayou La Batre, Ala.

M.J. Bosarge, who lives near the shipyard, said at least one of the riverboats had done considerable damage to the dock.

"You really want to get them secured because with wind and rain like this, the water is constantly rising," Bosarge said. "They could end up anywhere. There's no telling where they could end up."

In Orange Beach, Ala., towering waves crashed onshore Tuesday as Crystal Smith and her young daughter, Taylor, watched. They drove more than an hour through sheets of rain and whipping wind to take in the sight.

"It's beautiful, I love it," Crystal Smith said. "But they are high. Hardly any of the beach isn't covered."

Capt. Michael Thomas, an Orange Beach fishing guide, was out securing boats and making other last-minute preparations. He estimated up to 13 centimetres of rain had fallen in as many hours.

"I'm as prepared as I can be," Thomas said.

A couple miles away in Gulf Shores, Ala., waves crashed over the end of the long fishing pier at Gulf State Park. Some roads in the town already were covered with water.

Historic flooding, rainfall expected

Stacy Stewart, a senior specialist with the National Hurricane Center, said Tuesday that people should continue to take the storm seriously since "devastating" rainfall is expected in large areas. He said people could drown in the flooding.

"This is going to be historic flooding along with the historic rainfall," Stewart said. "If people live near rivers, small streams and creeks, they need to evacuate and go somewhere else."

Donald Jones, a National Weather Service meteorologist in Louisiana, said Sally could unleash flooding similar to what Hurricane Harvey inflicted in 2017 when it swamped the Houston metropolitan area.

Mississippi Gov. Tate Reeves said Tuesday that people in the southern part of the state should prepare for heavy rain and the potential for flash flooding, even if the hurricane comes ashore to the east. He said about 120 people were in shelters in Mississippi.

After making landfall, Sally was forecast to cause flash floods and minor to moderate river flooding across inland portions of Mississippi, Alabama, northern Georgia and the western Carolinas through the rest of the week.

Alabama Gov. Kay Ivey urged residents near Mobile Bay and low-lying areas near rivers to evacuate if conditions still permitted a safe escape. The National Hurricane Center predicted storm surge along Alabama's coast, including Mobile Bay, could reach 2.1 metres above ground.

"This is not worth risking your life," Ivey said during a news conference Tuesday.

Along the I-10 highway that runs parallel to the Gulf Coast from Louisiana to Florida, rain grew heavier Tuesday in places like Gautier and Pascagoula, Miss. Businesses along highway exits appeared to be largely closed.

In Gulfport, Miss., white plastic bags hung over some gas station pumps to signal they were out of fuel. Along a bayou that extended inland from the Gulf, three shrimp boats were tied up as shrimpers and others tried to protect their boats from waves and storm surge. Most boat slips at Gulfport's marina were empty, and many businesses had metal storm shutters or plywood covering the windows.

Louisiana likely to be spared worst of storm

U.S. President Donald Trump issued emergency declarations for parts of Louisiana, Mississippi and Alabama on Monday, and tweeted that residents should listen to state and local leaders.

The threat to Louisiana was easing as officials in some areas reversed evacuation orders that had been issued for areas feared to be at risk of flooding from Sally. In New Orleans, government offices and public school operations were slated to reopen Wednesday.

The southwestern part of the state, particularly Lake Charles, was pummelled by Hurricane Laura on Aug. 27. An estimated 2,000 evacuees from that storm are still sheltered in New Orleans, mostly in hotels.

The extraordinarily busy hurricane season — like the catastrophic wildfire season on the West Coast — has focused attention on the role of climate change.

Scientists say global warming is making the strongest of hurricanes, those with wind speeds of 177 km/h or more, even stronger. Also, warmer air holds more moisture, making storms rainier, and rising seas from global warming make storm surges higher and more damaging.

In addition, scientists have been seeing tropical storms and hurricanes slow down once they hit the United States by about 17 per cent since 1990, and that gives them the opportunity to unload more rain over one place, as 2017's Hurricane Harvey did in Houston.