Threats of 3-5 inches of rain — and the possibility of 8 inches in some places — have people in northwest Florida bracing for flooding from Tropical Storm Colin. The storm is forecast to hit the area Monday afternoon and then move north along the East Coast.

After forming in the Gulf of Mexico last week, Colin now packs sustained winds close to 50 mph and could strengthen, the National Hurricane Center said in an update this morning. Tropical storm-force winds extend for some 185 miles from Colin's center.

On Monday, Florida Gov. Rick Scott declared a state of emergency in dozens of counties in the storm's path.

Local officials were handing out sandbags to residents, urging them to shore up entrances to their homes, according to member station WUSF in Tampa.

The NHC predicts that if the storm comes along with high tide, the storm surge could be 1-3 feet in the area from Indian Pass to Tampa Bay, and 1-2 feet from Tampa Bay south to Florida Bay. But a far larger area could feel Colin's effects, with forecasters saying heavy rains are likely from Mexico's Yucatan peninsula to southeastern Georgia and coastal areas of the Carolinas.

"The deepest water will occur along the immediate coast," the NHC says. "Surge-related flooding depends on the relative timing of the surge and the tidal cycle, and can vary greatly over short distances."

Hurricane season officially started last week — and the NHC says Colin's emergence as a tropical storm marks the earliest that a third named storm has arisen in the Atlantic region. This season's two earlier storms were Alex, which formed in January, and Bonnie, which hit South Carolina over Memorial Day weekend.

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