Hurricane and storm surge warnings have been issued for New Orleans, and it's possible Nate will make landfall in the same place Katrina did in 2005 - though Nate will arrive with much less size and strength, and it will move away quickly.
It is reported that the power of the storm grew from a category 1 to a tropical level of a hurricane last night.
The Democrats True Blue Gala, formerly known as the Jefferson-Jackson Dinner but changed this year to remove the former slaveholders' names, was held at the Riverside Hilton in New Orleans on Friday.
Storm surge warnings were issued in Morgan City, La., to the Alabama/Florida border, and the northern and western shores of Lake Pontchartrain.
Louisiana and MS officials declared states of emergency, and Louisiana ordered some people to evacuate coastal areas and barrier islands ahead of Nate's expected landfall.
Residents are especially wary after Hurricane Harvey flooded huge swaths of Houston in late August with more than 50 inches (127 cm) of rain.
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The Bankhead Tunnel, a major downtown thoroughfare that passes under the Mobile River, was closed because of the hurricane, emergency officials and a reporter with CNN affiliate WPMI tweeted.
Hurricane Nate is expected to strengthen to a Category 2 storm before it makes landfall late Saturday night or early Sunday morning.
The storm's reach will be wide, CNN meteorologist Chad Myers said, with strong winds affecting population centers from New Orleans to Panama City, Florida. Some beachfront hotels and casinos were evacuated.
"We are ready for whatever Nate brings our way", Mr Landrieu said of forecasts that Nate could dump 3-6in of rain on the region - with isolated totals of up to 10in. About 2,000 people were affected.
While it is too early to determine if Nate will strengthen into an hurricane as it approaches the US mainland, the National Hurricane Center said a hurricane watch was in effect for a northeast portion of the Yucatan Peninsula. Additionally, Nate's anticipated landfall will have an impact on several flights along the Gulf Coast.
According to an advisory from the National Weather Service office in Birmingham, Central Alabama could se between 3 and 4 inches of rain, with sustained winds up to 40 miles per hour, and gusts in the high 50s. A 7 PM curfew remains in effect for the metropolitan area of New Orleans. "The seas get agitated, get built up around Nate because of the wind and they start migrating west toward the Texas coastline", Speece said. It's expected to continue northward, clipping the Yucatan Peninsula, and then head through the Gulf of Mexico, where it's likely to hit warm patches of water that will help it intensify into a hurricane.