Debby made landfall as a hurricane on the coast of Florida earlier today and has since weakened to a Tropical Storm, but a catastrophic flooding event continues to unfold along the U.S. East Coast with some portions of the southeast coast likely to get 2-3 feet of rain which would be historic on top of catastrophic.
Debby continues to move over land, and based on surface synoptic and radar observations the center is estimated to be near the
Florida/Georgia border. Debby continues to move through a weakness in the subtropical high, and the forward motion has slowed to only about 5 kts. The cyclone is expected to turn eastward, while moving quite slowly, in a region of weak steering currents for the next couple of days. According to the National Hurricane Center, this motion should bring the center of the system back over water by late Tuesday. In around 72 hours, a mid-level ridge to the east of Debby is forecast to build somewhat, and as a result, the center should move inland over South Carolina and turn northward and northeastward over the eastern U.S. for the remainder of the week.
The tropical cyclone should continue to weaken while it moves over land for the next day or so. By late Tuesday, assuming the center of the system moves back over water, some re-intensification is forecast. The NHC forecast continues to show only modest restrengthening due to the uncertainties, although they say this may be conservative.
Given the sluggish forward motion of Debby, extremely large amounts of rainfall over the Southeastern U.S. is anticipated.
The National Hurricane Center is sharing these three key messages:
1. Potentially historic heavy rainfall across southeast Georgia and the coastal plain of South Carolina through Saturday morning will likely result in areas of catastrophic flooding. Heavy rainfall will likely result in considerable flooding impacts from portions of central and northern Florida and across portions of central and northeast North Carolina through Saturday morning.
2. Dangerous storm surge and tropical storm conditions will spread northward along the southeast U.S. coast from northeastern Florida to North Carolina through the middle of the week. Storm Surge and Tropical Storm watches and warnings have been issued for portions of these areas. Residents in the Storm Surge watch and warning area should follow any advice given by local officials.
3. In portions of Florida where Debby has passed, deadly hazards remain, including downed power lines and flooded areas. Ensure generators are properly ventilated to avoid carbon monoxide poisoning. Exercise caution when using chainsaws and power tools, and drink plenty of water to avoid heat exhaustion.
Turn around, don’t drown. NEVER drive through flood waters!! https://t.co/DnUlexsjqs
— the Weatherboy (@theWeatherboy) August 5, 2024
Numerous watches and warnings remain in effect for Debby above and beyond the Flood Watches and Warnings that are up. A Storm Surge Warning is in effect for the Georgia and South Carolina coast from the Mouth of the St. Mary’s River to South Santee River South Carolina; a Storm Surge Watch is in effect for the South Carolina and North Carolina coast from north of South Santee River to Cape Fear, North Carolina. A Storm Surge Warning means there is a danger of life-threatening
inundation, from rising water moving inland from the coastline. A Storm Surge Watch means there is a possibility of life-threatening inundation, from rising water moving inland from the coastline, in the indicated locations during the next 48 hours.
A Tropical Storm Warning is in effect for St. Augustine, Florida to South Santee River, South Carolina while a Tropical Storm Watch is in effect for the area North of South Santee River, South Carolina to Cape Fear, North Carolina. A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area within 36 hours. A Tropical Storm Watch means that tropical storm conditions are possible within the watch area, generally within 48 hours.
“Interests elsewhere along the southeastern coast of the United States should monitor the progress of this system. Additional watches and warnings will likely be required later today,” said the National Hurricane in a statement this evening.
Numerous hazards exist from Debby, even as a tropical storm. Damaging winds, storm surge, epic rain, tornadoes, and rough surf are all likely to continue.
Tropical storm conditions are expected over portions of the tropical storm warning area along the Florida and Georgia Atlantic coast through tonight. Tropical storm conditions are expected along the coast of South Carolina within the tropical storm warning area by late tonight or early Tuesday.
The combination of storm surge and tide will cause normally dry areas near the coast to be flooded by rising waters
moving inland from the shoreline. The water could reach 2-4 feet from the mouth of the St. Mary’s River to Cape Fear, North Carolina if the peak surge occurs at the time of high tide.
Debby is expected to produce additional rainfall totals of 6-12″, with maximum amounts of 18″, across portions of central and northern Florida as well as central and northeast North Carolina through Wednesday morning. This rainfall will likely result in areas of considerable flash and urban flooding, with significant river flooding expected. Across portions of southeast Georgia, the coastal plain of South Carolina, and southeast North Carolina, 10-20″ of rain, with local amounts to 30″ through Saturday
morning.
The National Hurricane Center warns, “This potentially historic rainfall will likely result in areas of catastrophic flooding.”
A few tornadoes are possible over southeastern Georgia and coastal South Carolina this evening through Tuesday.
Swells generated by Debby are expected to affect much of the Gulf coast of Florida through tonight. Swells will continue to affect the Southeast U.S. coast through the middle of the week. These conditions are likely to cause life-threatening surf and rip
current conditions. Even expert swimmers and surfers should avoid the ocean until the hazards from Debby completely pass.
