Zeta expected to regain strength, make landfall as a Category 1 hurricane outside New Orleans

Tropical Storm Zeta weakened on Tuesday after making landfall in Mexico with sustained winds of 80 mph, but forecasters said it could regain strength as it makes its way toward Louisiana later this week.

Zeta made landfall as a Category 1 hurricane just north of Tulum, an ancient Mayan city located along Mexico's Yucatan Peninsula, Monday night.

As of Tuesday night, it had restrengthened to 70 mph and was moving northwest at about 15 mph.

The National Weather Service issued hurricane warnings for parts of coastal Louisiana and Mississippi, and tropical storm watches and warnings between Louisiana and the Florida Panhandle. Coastal cities along the northern Gulf Coast were also placed under hurricane and storm surge watches, the NWS said, noting threats of coastal flooding, heavy rain and possible tornadoes.

Zeta, the 27th named storm of the season, is expected strengthen over the next 24 hours leading up to landfall in the U.S. Wednesday evening. It's expected to touch down as a Category 1 hurricane just south of New Orleans.

Meteorologist said the storm could bring strong winds, up to 8 feet of storm surge and up to 6 inches of rain in some areas. Isolated tornadoes are also possible, adding to the possibility of widespread damage and power outages in parts of Mississippi and Alabama.

Louisiana Gov. John Edwards declared a state of emergency in anticipation of the storm Monday night. He said he issued the order despite uncertainty surrounding the storm's final path, and urged residents to follow the guidelines.

"While there is some uncertainty in Zeta's track, it is likely that Louisiana will see some impacts from this storm, and the people of our state need to take it seriously. It's easy to let your guard down late in the hurricane season, but that would be a huge mistake," Edwards said.

He said state officials were already assisting local authorities with "critical items like pumps, generators and food and water" for first responders.

"We stand ready to expand that assistance as needed," Edwards said in a statement. "Everyone should be monitoring the news for information and should heed any direction they get from their local leaders."

Forecasters said Zeta will most likely speed off to toward the Northeast and weaken quickly after landfall late Wednesday.

The storm's remnants could get swept up with another storm system as it leaves the area, potentially bringing heavy rain in areas between the Tennessee Valley into the Northeast, meteorologists said.

ABC News' Melissa Griffin contributed to this report.