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A hurricane watch was posted for a 420-mile-long swath from St. Marks in the Florida Panhandle, just south of Tallahassee, to New Orleans and Morgan City, La.

Authorities ordered or strongly urged hundreds of thousands of residents and tourists to evacuate coastal areas of the Florida Panhandle, Alabama, Mississippi and Louisiana. Schools were closed in New Orleans and parts of Florida, Mississippi and Alabama, and some areas started opening shelters. Panama City Beach was deserted at dawn Tuesday.

Will the killer storm hit the Gulf Coast and beyond? How are coastal towns reacting? And how powerful will its punch be? Greta has the latest from the storm watch.

These stories and much more...

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