(CNN) -- A soggy weekend is in store for parts of the U.S. Gulf Coast as Tropical Storm Karen churns in the central Gulf of Mexico.
The National Hurricane Center issued a hurricane watch for the area from Grand Isle, Louisiana, to west of Destin, Florida. The center of the storm is forecast to be near the coast within that area Saturday.
A tropical storm warning is in effect from Grand Isle to the mouth of the Pearl River on the Louisiana-Mississippi line. Karen could strengthen to a hurricane by Saturday night, the hurricane center said, although the storm's tracking map never shows Karen becoming a hurricane.
The storm, centered about 275 miles south-southwest of the mouth of the Mississippi River about 8 a.m. ET Friday, prompted the Federal Emergency Management Agency to recall some of its workers furloughed during the government shutdown. The agency also reactivated its Hurricane Liaison Team at the National Hurricane Center in Miami. FEMA officials in the Atlanta and Denton, Texas, offices are monitoring Karen.
"At all times, FEMA maintains commodities, including millions of liters of water, millions of meals and hundreds of thousands of blankets, strategically located at distribution centers throughout the United States, including in the Gulf Coast region, that are available to state and local partners if needed and requested," the agency said in a statement.
The hurricane center said it, too, would be unaffected by the government shutdown as Karen approaches.
"The National Hurricane Center is fully operational ... and has all of its resources available to it," spokesman Dennis Feltgen said in an e-mail. "The government shutdown will not inhibit NHC from providing its mission."
Louisiana Gov. Bobby Jindal declared a statewide state of emergency. Florida Gov. Rick Scott declared a state of emergency in 18 counties.
New Orleans officials released a statement asking residents to "monitor weather conditions and stay alert." The city is included in the tropical storm watch area.
Karen formed between Cuba and Mexico's Yucatan Peninsula. It was producing maximum sustained winds of 60 mph Friday morning, with higher gusts. The storm slightly weakened overnight.
The storm was moving north-northwest at 10 mph Friday morning, the hurricane center said. It is expected to turn north Friday and then northeast on Saturday, the center said.
"Karen is expected to produce rainfall amounts of 4 to 8 inches over portions of the central and eastern Gulf Coast through Sunday night," the hurricane center said. "Isolated storm total amounts of 12 inches are possible."
Storm surges also are a concern. If peak surges coincide with high tide, water could reach 3 to 5 feet above ground from the mouth of the Mississippi River in Louisiana to Alabama's Mobile Bay, the center said.
"The combination of storm surge and the tide will cause normally dry areas near the coast to be flooded by rising waters," the center said.