Updated: 1 p.m., Saturday

Hurricane Nate is gaining strength and speed over the Gulf of Mexico and is expected to make landfall along the central U.S. Gulf Coast as a Category 2 storm Saturday evening.

“It is moving at an extremely fast rate, said Louisiana Gov. John Bel Edwards at a briefing Saturday, “almost unheard of for a storm of this type.”

In its 1 p.m., CDT advisory, the National Hurricane Center said the Category 1 storm was located about 100 miles south of the mouth of the Mississippi River and headed north northwest at 25 mph. It had maximum sustained winds of 90 mph.

“This is a very strong storm,” Edwards said.

He asked that residents to be prepared to ride out the storm by 3 p.m., local time Saturday, keeping off the roads. That was five hours earlier than the time Edwards had requested a day earlier.

A hurricane warning is in effect from Grand Isle near the southern tip of Louisiana stretching to the Alabama/Florida border, including metropolitan New Orleans and the Mississippi Gulf Coast.

“Everybody in this area needs to prepare for hurricane force winds,” said Mike Brennan, senior hurricane specialist with the NHC, adding, “we are very concerned about storm surge.”

A storm surge warning covers much of the region, including around Lake Pontchartrain in the New Orleans area. Forecasters said flood waters could reach 11 feet above ground level, “so that is life-threatening,” Brennan said.

“The deepest water will occur along the immediate coast near and to the east of the landfall location, where the surge will be accompanied by large and destructive waves,” the NHC said in its advisory.

Grand Isle is under a mandatory evacuation, as are parts of New Orleans and other parts of southeastern Louisiana are voluntary evacuation areas. Edwards said emergency shelters are open in every parish where evacuations have been called.

“It is critical that everyone told to evacuate, do it now,” Edwards said at the 12 p.m. CDT briefing Saturday. He said three quarters of hurricane fatalities occur due to water, and motorists could be fooled by deceptively deep water.

A mandatory curfew begins at 7 p.m., local time Saturday in New Orleans and lasts “until the risk has passed,” said the city police department in a statement.

Officials in Mississippi recommended evacuations for all low-lying areas and for people living near waterways and in mobile homes.

On Friday President Trump approved an emergency declaration for Louisiana, authorizing the Department of Homeland Security and FEMA to coordinate relief efforts.

The governors of Florida, Alabama and Mississippi have all declared states of emergency ahead of the storm.

“Regardless of where the storm makes actual landfall, we face the possibility of widespread power outages and storm surge flooding,” Mississippi Governor Phil Bryant said in a statement. “I ask everyone to please have a plan, especially those that live in mobile homes and low-lying areas.”

Earlier in the week, Nate was a weaker Tropical Storm, but heavy wind and rain and subsequent flooding were blamed for several deaths in Nicaragua, Costa Rica, Honduras and El Salvador.

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