SAVANNAH, Ga. - Nervous residents rushed to buy plywood and generators while emergency officials in Georgia, Florida and the Carolinas weighed possible evacuations Tuesday as Tropical Storm Hanna was expected to shift toward a tough-to-predict landfall along the southern Atlantic coast by the end of the week.

Florida Gov. Charlie Crist declared a state of emergency as Hanna, downgraded from hurricane status Tuesday but with ample time to regain strength, was forecast to turn to the northwest from the Bahamas. Emergency officials in Georgia and South Carolina went into 24-hour alert mode.

In Savannah, which hasn't seen a direct hit from a major hurricane in more than a century, Janey Miley took her 15-year-old daughter to Home Depot at lunchtime Tuesday for an impromptu lesson in hurricane preparedness.

They waited in a busy checkout line with a 5-gallon gas can, a circular saw and 10 sheets of plywood in case they needed to board up the windows of their home on nearby Tybee Island. A steady flow of customers pushed carts stocked with everything from batteries to 5,000-watt generators.

"We've never really bought plywood, but it seemed like maybe we'd better do it this time," said Miley, 43, who had also booked hotel reservations in Columbia, S.C., in case her family needed to evacuate.

The National Hurricane Center predicted Hanna would most likely come ashore as a hurricane between Friday and Saturday somewhere between the east coast of Florida and the North Carolina coast. Forecasts Tuesday showed the storm making landfall near the Georgia-South Carolina border.

Hanna was packing winds of 65 mph Tuesday evening as it drifted over the Bahamas. But the Hurricane Center said it could intensify back to hurricane strength Wednesday, when the storm was expected to turn to the northwest.

Local emergency officials for Savannah and surrounding Chatham County urged residents to have an evacuation plan ready. But no decisions on voluntary or mandatory evacuations were expected before Wednesday.