Edouard strengthens, could become hurricane Tuesday

(CNN) -- Tropical Storm Edouard picked up momentum early Tuesday as it neared the Texas and Louisiana coasts, forecasters said.
The National Hurricane Center said the storm was moving west-northwest in the Gulf of Mexico and is expected to reach the coast near the Texas-Louisiana state line by midday Tuesday.
A tropical storm warning was in effect from the mouth of the Mississippi River west to Port O'Connor, Texas. The warning means that tropical storm conditions are expected in the warning area within 24 hours.
A hurricane watch, which means hurricane conditions are possible within 36 hours, was in effect from west of Intracoastal City, Louisiana, to Port O'Connor.
The U.S. Census Bureau on Monday said more than 5.4 million people could be affected by the storm, which started as a depression in the Gulf of Mexico early Sunday afternoon.
At 2 a.m. ET Tuesday, the center of the tropical storm -- the fifth one this season -- was about 90 miles (145 km) southeast of Port Arthur, Texas and about 120 miles (190 km) east of Galveston, Texas, the hurricane center said.
The storm was moving west at nearly 10 mph (17 km/hr), while its maximum sustained winds were near 60 mph (95 km/hr), with higher gusts, the center said. Tropical storm force winds extended up to 70 miles (110 km) from the center.
The storm was moving west at nearly 8 mph (13 km/hr), while its maximum sustained winds were near 60 mph (95 km/hr), with higher gusts, the center said. Tropical storm force winds extended up to 70 miles (110 km) from the center.
Edouard is expected to dump up to 5 inches of rain along the Louisiana coast, and "maximum amounts of 10 inches are possible over southeastern Texas," the hurricane center advisory said.
As the storm approached, Galveston Mayor Lyda Ann Thomas said the city has activated its emergency management center.
The Gulf Coast city's Web site warned residents to create an evacuation plan in case they have to flee the storm.
Thomas said the city hall will be closed Tuesday for the storm but emergency workers would be working and ready.
Authorities in Houston, about 50 miles north of Galveston, also said they were prepared for the storm.

"Everything is in place," said Ed Emmett, director of the office of Homeland Security in the county that encompasses Houston.
Emmett said 200 buses, 19 ambulances, numerous shelters and helicopters were ready in case there is need for the evacuation of homes or hospitals.