Debby A Flood Threat From Carolinas To Northeast | Weather.com (2024)

Tropical Storm Debby won't last much longer, but its moisture and remnant spin will wring out locally flooding rain from the Carolinas to New England through early Saturday.

Current status: Debby is centered near the South Carolina coast, moving slowly. It's producing scattered bands of heavy rain from eastern Georgia and South Carolina to North Carolina and southern Virginia, prompting some flash flood warnings, shown by the green polygons in the map below.

A​ tornado watch remains in effect for parts of the eastern Carolinas until 11 p.m. EDT.

Where it's headed: After its center is back over land, D​ebby's remnant will move faster and sweep through the mid-Atlantic and interior Northeast Friday into early Saturday while interacting with a pair of fronts, resulting in pockets of locally heavy rain across those regions.

Rainfall flood threat:

Southeast

B​ands of locally heavy rain are likely along and to the east of Debby's center through at least Thursday night in parts of the Carolinas and Virginia. These bands could lead to additional flash flooding and could worsen ongoing river flooding.

T​he areas most at risk for additional heavy rain Thursday are shown in the red and pink contours, below.

T​his threat should become more isolated by Friday, though river flooding may linger for days in the hardest hit areas.

N​ortheast

P​arts of the region have been soaked multiple times this week either by rounds of severe thunderstorms, or clusters of heavy rain, such as what affected the New York City Tri-state area Tuesday.

W​hile pockets of locally heavy rain are possible in the Northeast through Thursday night, the main threat for more widespread heavy rainfall will be from early Friday into Friday night, particularly from the Appalachians to upstate New York and Vermont, in the areas shaded in red on the map below.

A​bout a month ago, the remnant from what was once Hurricane Beryl triggered major flash flooding from upstate New York to Vermont, northern New Hampshire and Maine, washing out roads and flooding some towns.

If you live in a low-lying flood-prone area, stay alert and follow the latest updates and warnings. Never attempt to drive through a flooded stretch of road or around barriers that signal a road closure. Over half of deaths in floods happen in vehicles, according to NOAA statistics.

H​ow much more rain:

• S​outh Carolina and southeast North Carolina: An additional 3 to 9 inches with locally higher amounts is possible. Storm totals including what has already fallen could be as high as 25 inches in eastern South Carolina and 15 inches in southeast North Carolina.
• P​iedmont of South Carolina to Virginia: Totals could be 3 to 7 inches, with locally higher amounts up to 10 inches possible.
• M​aryland to upstate New York and Vermont: These areas could see 2 to 4 inches of rain, with local amounts up to 6 inches.

Wind threat: Tropical storm warnings cover parts of South Carolina to southeast North Carolina as far north as Surf City, as shown below. The warnings include Charleston and Myrtle Beach.

Tropical storm conditions (39 to 73 mph sustained winds) are possible through early Thursday in these areas.

Stronger wind gusts over 40 mph, coupled with increasingly soaked ground from heavy rain, could trigger more power outages, downed trees and tree damage.

Storm surge threat: Inundation from storm surge could reach 1 to 3 feet above ground level if the peak surge arrives at high tide from the northeast South Carolina coast to Ocraco*ke Inlet, including the lower Neuse and Pamlico Rivers. High tides along the coast are generally around 10 a.m. and p.m. EDT.

I​solated tornado threat: Wednesday night, a tornado or two could spin up from northeast South Carolina into eastern North Carolina.

Thursday's chance for a few tornadoes will be in eastern North Carolina and southeast Virginia.

W​e can't rule out an isolated tornado again Friday from near Chesapeake Bay to the Delaware Valley and New Jersey.

R​ecap

Debby formed from a tropical wave the National Hurricane Center first started highlighting for possible development in the Atlantic on July 26.

It then strengthened into Tropical Storm Debby late on Aug. 3 in the southeast Gulf of Mexico.

D​ebby intensified into a hurricane at 11 p.m. on Aug. 4 ahead of its Category 1 landfall near Steinhatchee, Florida, on the morning of Aug. 5. That was just 15 miles away from where Hurricane Idalia made landfall along Florida's Big Bend last August.

Debby then moved inland over north Florida into southern Georgia, slowing its forward speed, before emerging back over the ocean just off the coast of South Carolina on Aug. 6.

B​y that time, Debby had begun ingesting some dry air, which not only had reduced the coverage of heaviest rainbands, but also limited its potential to restrengthen while over water.

R​ainfall

D​ebby dumped over 10 inches of rain over many areas from western and northern Florida into eastern Georgia and South Carolina. The peak rainfall tally was 19.67 inches near Lake City, Florida.

F​lash flooding and river flooding swamped some homes, washed out roads and stranded vehicles. Among the hardest hit areas were parts of Manatee and Sarasota Counties, Florida; Live Oak, Florida; near Statesboro, Georgia; and Colleton County, South Carolina, where a 20-acre pond was drained after two holes were punched in dikes surrounding the pond.

The Manatee River just east of Bradenton, Florida (Rye Bridge), topped its previous record flood crest from July 21, 1962. The Canoochee River near Claxton, Georgia, topped its previous record crest that stood since New Year's Day 1925.

Those were just two of over a dozen river gauges that rose to moderate or major flood stage from Florida to the Carolinas.

S​torm Surge

D​ebby pushed Gulf water into the Florida coast as a tropical storm and hurricane, adding to the storm's water impact.

T​his storm surge hit some of the same areas affected by Idalia almost one year ago, but likely not nearly matching the 8 to 12-foot inundation above ground of Idalia from Keaton Beach to Steinhatchee.

C​edar Key, Florida, had a storm surge of up to 5.8 feet above normal tide levels, equating to a peak inundation of about 4.65 feet above ground level as Hurricane Debby made landfall on Aug. 5.

F​arther south, the combination of a new moon, high tide and Debby lead to a peak inundation at Ft. Myers, Florida, higher than Idalia and Irma, according to WINK-TV meteorlogist Matt Devitt, at just over 3 feet above ground level.

T​he surge and battering waves ate away at the side of the Howard Frankland Bridge over Old Tampa Bay, and chewed up a section of Harbor Drive in Venice, Florida.

W​inds

D​ebby produced wind gusts of at least 70 mph near Chiefland (76 mph), Dania Beach (73 mph) and near Palmetto (70 mph).

G​usts over 60 mph were clocked at Cedar Key, Sarasota-Bradenton Airport (63 mph) and at Folly Beach, South Carolina (63 mph).

A​t the peak of the storm, over 300,000 customers were without power from Florida to the Carolinas.

T​ornadoes

A​s with most landfalling hurricanes and tropical storms, some tornadoes were spawned across the Southeast within Debby's rainbands.

A​t least four tornadoes were spawned in the Lowcountry of South Carolina on the night of Aug. 5. That included an EF1 tornado in Edisto Beach and another EF1 twister in Moncks Corner.

T​wo days later, at least one, possibly two separate tornadoes spin through eastern North Carolina, damaging homes in Sampson County and tossing debris onto a highway in Pender County, north of Wilmington.

M​ORE ON WEATHER.COM: Photos From Debby's Damage