NEW ORLEANS (Reuters) – The U.S. Gulf Coast braced for Hurricane Nate to make landfall east of New Orleans as a Category 2 storm on Saturday evening, threatening parts of Louisiana, Mississippi and Alabama with torrential rain, flooding and winds of 100 miles per hour (160 km per hour).

Nate, the fourth major storm to strike the United States in less than two months, killed at least 30 people in Central America before entering the warm waters of the Gulf and bearing down on the U.S. South.

The hurricane should make landfall as early as 8 p.m. Saturday (0100 GMT Sunday), New Orleans Mayor Mitch Landrieu said. Low-lying southeastern Louisiana, just south of the city, was the likely target, the U.S. National Hurricane Center said.

“We’re in the fight now. The storm is on us,” Landrieu told reporters at a briefing on Saturday afternoon, adding that conditions were expected to rapidly deteriorate.

Still a Category 1 hurricane, Nate was approaching the mouth of the Mississippi River at 4 p.m. Central time, moving north-northwest at 23 mph (37 kph), the NHC said.

Maximum sustained winds were hovering at about 90 mph (145 kph), with higher gusts, but the hurricane could still strengthen to Category 2 before landfall.

The NHC issued a hurricane warning from Grand Isle, Louisiana to the Alabama-Florida border. A state of emergency was declared for more than two dozen Florida counties and for the states of Alabama, Louisiana and Mississippi.

New Orleans, about 60 miles (97 km) north of Grand Isle, evacuated some residents from areas outside its levee system as the storm approached. The winds could cause significant power outages in the city, Landrieu said.

Landrieu declared a mandatory curfew in the city from 7 p.m. Saturday to 7 a.m. Sunday, and urged residents and an estimated 40,000 visitors to shelter in place overnight, when the worst conditions are expected.

“We have been through this many, many times. There is no need to panic,” Landrieu told reporters, alluding in part to Hurricane Katrina, which triggered severe flooding in New Orleans and killed hundreds of people in August 2005.

But residents of the city known as the “Big Easy” were taking Nate in stride. At a Lowe’s hardware store in the St. Roch area of New Orleans, there were short lines around midday and plentiful supplies of propane, generators and plywood.

“They don’t start boarding up until it’s a Category 3,” said employee Paula Clemons. “We’re used to floods. Comes with the territory.”

That said, for some residents of New Orleans, memories of Katrina and Hurricane Betsy in 1965 were still vivid.

By Saturday afternoon, as Nate’s outer band pelted sheets of rain on the city, residents had filled 13,000 sandbags at a fire hall on Elysian Fields Drive, just one of five such sandbag depots in the city.

“I’ve been through Betsy and Katrina. Ain’t no way they’re going to stop this water,” said Antoine Turner, 55, as he heaved sandbags into his half-ton truck, hoping to protect a building where he was preparing to open a soul food restaurant. “Best thing to do is just pray.”

In Belle Chasse, located on a slip of land that follows the last bend of the Mississippi River as it flows into the Gulf, Derrick Ulloa, 27, and Ryan Hunt, 28, faced a 20-foot (6-m) concrete wall designed to keep the Mississippi River off their doorsteps.

“We’re not worried about it,” said Hunt, as he and Ulloa organized jerry cans of gasoline to power a generator that will keep their fridges and an air conditioner running through the storm.

ALABAMA BRACES

After hitting the U.S. Gulf Coast, the storm is likely to veer to the northeast and cut through Alabama, the state likely to be hit hardest. Republican Governor Kay Ivey urged residents in areas facing heavy winds and storm surges to take precautions.

Between four and eight inches (10 cm and 20 cm) of rain will fall from far southern Mississippi and northern and western Alabama to northern Georgia, middle and eastern Tennessee, western North Carolina and the Virginia Panhandle, AccuWeather forecast.

Nate will mark the fourth major storm to slam the United States in the current hurricane season, following Harvey, Irma and Maria, which devastated Texas, Florida and Puerto Rico, respectively.

But as a Category 1 or 2, the weakest in the five-category ranking used by meteorologists, Nate may not pack the same punch as its predecessors.

Major shipping ports across the central U.S. Gulf Coast were closed to inbound and outbound traffic on Saturday, as Nate intensified and storm surges of up 11 feet (3.74 m) were expected at the mouth of the Mississippi River.

The storm has curtailed 92 percent of daily oil production and 77 percent of daily natural gas output in the Gulf of Mexico, more than three times the amount affected by Harvey.

Workers had been evacuated from 301 platforms and 13 rigs as of Saturday, said the U.S. Bureau of Safety and Environmental Enforcement.

Before heading north into the Gulf, Nate brushed Mexico’s Yucatan peninsula, home to beach resorts such as Cancun and Playa del Carmen, the NHC said.

The storm doused Central America with heavy rains on Thursday, killing at least 16 people in Nicaragua, 10 in Costa Rica, two in Honduras and two in El Salvador.

Thousands were forced to evacuate their homes and Costa Rica’s government declared a state of emergency.