The first significant threat from a named storm this hurricane season is on the way to the northern Gulf of Mexico coast.
The 11th named storm, Karen, formed early Thursday as a strong tropical storm about 500 miles south of the mouth of the Mississippi River, according to the National Hurricane Center (NHC). The storm with 65 mph winds was moving to the north northwest at 12 mph.
With further strengthening anticipated to near or at hurricane strength, NHC posted hurricane and tropical storm watches and warnings from southeast Louisiana and Mississippi across the Alabama and Florida Panhandle.
The hurricane watch is in effect from Grand Isle, La., to Indian Pass in the Florida Panhandle including the cities of Gulfport, Biloxi, Pascagoula, Mobile and Pensacoula. A tropical storm watch is in effect for parts of the Louisiana coast west of Grand Isle, including the New Orleans area with a warning including Lower Jefferson, Lower Plaquemines and Lower St. Bernard parishes.
Karen is expected to make a turn more toward the north with a decrease in forward speed during the next 48 hours ahead of an approaching cold front. This front will be the main determining factor on whether Karen will turn northeast over southern Mississippi or over southern Alabama and the Florida Panhandle.
On the current forecast track, the center of Karen will approach the northern Gulf Coast within the hurricane watch area on Saturday with hurricane and tropical storm conditions spreading onto the parts of southeastern Louisiana, coastal Mississippi and southwestern Alabama by late Friday and early Saturday.
"Karen will move around the periphery of the subtropical ridge during the next day or so and then accelerate northeastward ahead of a mid/upper-level trough. Karen should be involved with a frontal zone by day 4 (Monday) and absorbed by the front by day 5 (Tuesday)," said Michael Brennan, a senior hurricane specialist at the NHC.
The governors of Louisiana, Mississippi and Florida all declared at least partial states of emergency ahead of Karen on Thursday.
All coastal residents are strongly advised to be prepared to evacuate if ordered in the coming days ahead of this storm.