By Chris Baltimore
HOUSTON (Reuters) - Strong winds and heavy rain from Tropical Storm Debby reached the U.S. Gulf Coast on Sunday as the storm meandered on an uncertain track toward the Louisiana coast with 60 mph winds, the U.S. National Hurricane Service said.
Debby, the first named storm of 2012 to enter the Gulf of Mexico, was centered about 200 miles east-southeast of the mouth of the Mississippi River and was moving slowly northeast at around 5 mph at 1 p.m. CDT (1800 GMT). The storm was expected to strengthen into a hurricane by Tuesday night, the Miami-based center said.
The NHC predicted that Debby will turn west and come ashore on the eastern Louisiana coast early Thursday as a weak Category 1 hurricane. Louisiana Gov. Bobby Jindal declared a state of emergency ahead of the storm, citing possible inland flooding in some coastal parishes.
Other forecast models were skewed on Debby's ultimate destination, with some showing landfall in Florida and others predicting the Texas coast. Debby should remain nearly stationary for the next 12-24 hours and "the track beyond that time is highly uncertain" due to divergent models, the NHC said.
Debby has already disrupted nearly a quarter of Gulf offshore oil and natural gas production as big offshore operators like BP Plc and Royal Dutch Shell evacuated workers from offshore platforms in the path of the storm.
That number could climb in coming days, with Debby expected to enter some of the most prolific production areas of the Gulf, home to 20 percent of U.S. oil production and 6 percent of natural gas output.
A tropical storm warning was issued for the Louisiana coast from the Pearl River west to Morgan City, excluding the city of New Orleans and Lake Pontchartrain. Residents were warned to expect storm conditions within 36 hours.
"Tropical storm conditions are already near or over portions of the northeast Gulf Coast and are expected to reach the remainder of the warning area tonight," the forecasters warned.
The NHC extended the storm warning east to the Mississippi-Alabama border and along Florida's northwest coast to the Suwannee River.
The combination of storm surge and high tide could cause flooding in normally dry areas near the Louisiana coast, they said.
Debby could bring 5 to 10 inches of rain to the Gulf Coast from southeast Louisiana to the central west coast of Florida, with up to 15 inches in isolated areas.
The heaviest squalls were hitting Florida's Gulf Coast, where there were unconfirmed reports that a tornado had touched down on Saturday. Several Alabama beaches were closed due to rough surf.
If Debby hits Louisiana as a hurricane, the burden would fall most heavily on insurers State Farm and Allstate, which together underwrite 42 percent of the personal property insurance there, according to Fitch Ratings.
But the biggest impact of all could fall on the federal government, in flood claims that would go to the Federal Emergency Management Agency's National Flood Insurance Program.
The NFIP, still struggling with unsustainable debts in the wake of Hurricane Katrina in 2005, has almost 500,000 policies in Louisiana with an in-force value of $112.5 billion.
(Additional reporting by Ben Berkowitz in New York and Erwin Seba in Houston; Editing by Doina Chiacu and Marguerita Choy)