Maps show Tropical Storm Debby's path and forecast
Tropical Storm Debby gained strength Wednesday as it drifted over the Atlantic near the coastal Carolinas and was expected to turn back toward South Carolina for a second landfall, the National Hurricane Center said. It was forecast to then slowly make its way north, bringing heavy rainfall and flooding.
The storm was expected to reach the South Carolina coast by Wednesday night or early Thursday, the hurricane center said.
Forecasters said Debby, fueled by warmer coastal waters, would probably continue to strengthen somewhat before striking land again, after which it was expected to weaken as its center moves inland. After hitting South Carolina, Debby could move up the middle of North Carolina, through Virginia and into the Washington area by Saturday, the hurricane center said.
At 8 p.m. EDT on Wednesday, Debby was about 40 miles east-southeast of Charleston, South Carolina, and about 75 miles south-southwest of Myrtle Beach. The storm was crawling north at just 3 mph, with maximum sustained winds of 60 mph. Debby had slowed down over the course of the morning and initially gained some intensity — jumping from 45 mph winds reported earlier Wednesday — but that strengthening had since plateaued.
The storm's generally sluggish pace, now about the same as an average person walking, means Debby is lingering for a long time in places it passes over, making flood risks high across the regions in its path that could persist in some areas well into the weekend.
Forecasters anticipated tropical storm conditions would continue along the coast of South Carolina through Thursday night. They expected the storm to speed up on its track across the Carolinas on its way up into the Mid-Atlantic states, although they didn't expect those areas would be spared from the inundation.
Debby first hit land Monday morning as a Category 1 hurricane over Florida's Big Bend coast and left a trail of inundation in its wake despite weakening shortly after landfall.
Although forecasters said Debby would likely gain power while offshore, the strengthening should be moderate as long as it remains along its expected path near the coast, which would allow only limited interaction with warmer Gulf Stream waters. There was a possibility that Debby would become more organized, but its inner core remained undefined Wednesday afternoon, so that was unlikely.
As the storm gets faster on its way toward the Northeast later this week, meteorologists said Debby would most likely converge with a frontal zone farther up the East Coast — that essentially means it will cross over an atmospheric threshold and into a different air mass — and become an extratropical cyclone as it dumps rain on places as far north as upstate New York and Vermont.
Tropical cyclone is an umbrella term that encompasses tropical depressions, tropical storms and hurricanes, which differ based on their strength. An extratropical cyclone can be as weak as a tropical depression or as strong as a tropical storm, but unlike tropical cyclones, they are cold at the core and therefore can't quickly grow into a hurricane.
Storm surge forecast
The map below, updated Wednesday morning, shows the highest potential peak storm surge heights, including tides. Forecasters noted that the timing of peak surge and high tide in a given area, and whether they coincide or not, will ultimately determine how destructive the inundation will be.
Heavy rainfall totals dominate the forecast
Debby has moved markedly slowly since its initial landfall in Florida, and the hurricane center on Wednesday continued to forecast massive rainfall totals along its path. Forecasters said Wednesday morning that Debby was expected to produce an additional 3 to 9 inches of rainfall, with locally higher amounts potentially raising the upper boundary of that prediction to 25 inches in parts of South Carolina, and 15 inches in parts of southeastern North Carolina, through the end of the week.
As Debby shifts northeastward it is expected to touch an expansive area, bringing the risk of torrential rain and flooding as far north as New England through Saturday.
While the storm had already brought unprecedented rainfall to Georgia and South Carolina, officials in parts of Florida said they were grappling with the aftermath of record rainfall, too, and preparing for more throughout the week. The hurricane center said southeastern Georgia could be facing rainfall totals as high as 15 inches by Thursday, potentially exacerbating flood threats in areas that have already been inundated.
Places considerably farther north should brace for heavy rain and flooding, too, forecasters said. Areas from far-western South Carolina up through Virginia were expected to get as much as 7 inches of rainfall, with local amounts as high as 10 inches, through Friday, likely causing significant flash and urban flooding, according to the hurricane center.
Flooding forecasts were similar for a large swath of the East Coast from Maryland through upstate New York and Vermont, where meteorologists anticipated as much as 6 inches of rain could fall in some areas through Saturday morning.
