A slow-moving tropical depression was slogging toward the Gulf Coast Friday, packing walloping rains that could drench the region with up to 20 inches.
Tropical storm warnings were issued from Mississippi to Texas and Louisiana, including New Orleans.
The National Hurricane Center said the system will dump 10 inches to 15 inches of rain over southern areas along the Gulf, and as much as 20 inches in some spots.
Louisiana Gov. Bobby Jindal declared a state of emergency Thursday due to the threat of flash flooding. State climatologist Barry Keim said the system could drench the region with up to 20 inches of rain.
"We could see sustained winds of up to 20 to 30 miles per hour with even higher gusts along a significant portion of the coastal zone. So it's time to batten down the hatches and get ready to deal with this guy."
The depression also could become Tropical Storm Lee, the 12th named storm of the Atlantic hurricane season.
Forecasts were for landfall over the weekend on Louisiana's coast. The depression had maximum sustained winds of 35 mph Friday morning. It was drifting slowly north near 1 mph with the hurricane center predicting slow, possibly erratic motion.
"Wow. This could be a very heavy, prolific rainmaker," National Weather Service meteorologist Frank Revitte said.
According to a hurricane center chart, maximum sustained winds could reach 60 mph by Saturday, lower than hurricane strength of 74 mph.
As hurricane season is hitting its peak in the Atlantic, storm watchers were monitoring three disturbances.
Besides the Gulf depression, Tropical Storm Katia was spinning in open waters. It weakened from a hurricane Thursday, though forecasters said it would again grow stronger.
It was about 750 miles east of the northern Leeward Islands and moving west-northwest near 15 mph with maximum sustained winds early Friday near 70 mph.
It could regain hurricane strength this weekend but forecasters said it's too early to tell if it would hit the U.S. It was expected to pass north of the Caribbean.
In yet another system, a slow-moving low pressure system about 450 miles south of Nova Scotia, Canada, had a 60 percent chance early Friday of becoming a tropical cyclone in the next two days.
They all come on the heels of Hurricane Irene, which brought destruction from North Carolina to New England late last month.
Tegan Wendland in Baton Rouge, La., contributed to this report, which contains material from The Associated Press.