Hurricane Debby Impacts the Florida Big Bend

Figure 2. Satellite Loop of Hurricane Debby from NOAA/CIRA on August 5th

Rainfall Amounts

Debby brought widespread rainfall amounts of 2 to 7 inches across portions of the Florida Big Bend and southern Georgia with even higher amounts of 7 to 12 inches observed across the southeast Big Bend and the Suwannee River Basin. The rainfall gradient for Debby was much sharper than most typical tropical systems. The primary reason the gradient was so sharp across the forecast area was due to the sheared nature of the system. Westerly shear around 10 to 15 knots, and much drier air on the western periphery of Debby caused much of the rainfall and impacts wind wise to be on the eastern side of the circulation as seen in the animation just after landfall (Fig 2 above). 

Figure 3: Radar estimated rainfall amounts during Hurricane Debby

Wind Gusts

Wind gusts were not nearly as strong as what many folks in this area observed one year prior during Hurricane Idalia. Regardless, widespread wind gusts nearing 70 mph were observed/estimated to have occurred across much of Dixie and Lafayette counties in the southeast Florida Big Bend. Elsewhere across the forecast area, widespread 30 to 50 mph wind gusts were observed. Much of these strong wind gusts occurred early Monday morning and into the early afternoon. These gusts were strong enough to cause widespread power outages across the southeast Big Bend

Figure 4: Hurricane Debby max estimated wind gusts

Storm Surge

Debby brought storm surge inundation of approximately 3 to 5 feet above normally dry ground to portions of the southeast Florida Big Bend. These values brought widespread flooding to the immediate coastal strip and unfortunately flooded some homes/businesses that were affected by Idalia less than one year earlier. While these amounts did not cause damage as widespread/severe as Idalia, this storm served as another reminder that the Apalachee Bay and Nature Coast of Florida is one of the most surge prone areas of the country.

Figure 5. Graphic showing the peak surge of Debby at Cedar Key (just south of our forecast area in NWS Tampa's Area of Responsibility. Graphic used to show the large tidal variations across this part of the Gulf and the timing of Debby's surge.

River Levels

Widespread heavy heavy rain across the Suwannee, Withlacoochee, Fenholloway, and Aucilla River Basins from Debby brought widespread river flooding to the forecast area. However, more significant flooding, on the riverine front, was likely avoided across our rivers due to the sheared nature of Debby and the antecedent dry conditions in place across the southeast Florida Big Bend before Debby arrived. 

Figure 6. Suwannee River above Gopher River Confluence (in MHHW)	Figure 7. Steinhatchee River at Steinhatchee (in MHHW)	Figure 8. Fenholloway River at Foley
Figure 9. Suwannee River at Rock Bluff  near Bell - CR 340 (in NAVD88)	Figure 10. Suwannee River at Branford - US 27 (in NAVD88)	Figure 11. Suwannee River near Wilcox - US 19 (in NAVD88)
Figure 12. Aucilla River at Lamont (US 27)	Figure 13. Suwannee River at Luraville - SR 51 (in NAVD88)

Impacts Summary

The impacts summary from our local counties is available by clicking here. The link provides summarized impacts from local county emergency management and other local officials. It is not a full summary of impacts and it is possible some realized impacts from Debby are not listed here or are missing. A quick summary of these impacts revealed widespread to numerous power outages across the southeast Florida Big Bend and into south-central Georgia. Many downed trees were reported across the southeast Florida Big Bend and into south-central Georgia. Unfortunately there were at least 2 direct fatalities from Debby (in our forecast area) due to trees falling on structures and 2 indirect fatalities due to traffic accidents. In addition to the power outages, widespread flooding occurred across the southeast portions of the forecast area in Madison, Lafayette, and Dixie counties. One of the more damaging aspects of Debby was long term flooding that developed across southeast Madison county. In these areas, high ground water levels combined with the slow movement of water towards southeast parts of the county caused new areas of flooding as the water was moving into areas that already had been affected by extremely heavy rains. Additionally, higher water levels caused water to come up from scattered sinkholes in portions of the county inducing new flooded areas. Riverine flooding, though within the minor flood category on portions of the Middle and Lower Suwannee River, persisted for up to 3 weeks, inundating or isolating residential areas immediately adjacent to the river from near Branford, FL southward to Manatee Springs, FL. 

Figure 11. Debby about one to two hours after landfall as flooding rains overspread the region

Figure 12. Widespread down trees caused several road closes and incidents during landfall. Many segments of I-10 between Tallahassee and Lake City were closed due to fallen trees blocking interstate traffic.

Storm Photos

Various photos from around the forecast area due to Debby. These photos do not encompass all of the impacts and damages from Debby.

Figure 13. Extensive flooding in Madison County well after landfall	Figure 14. Extensive flooding in Madison County well after landfall)	Figure 15. Extensive flooding in Madison County well after landfall
Figure 16. Tree Damage in Jefferson County	Figure 17. Tree Damage in Jefferson County
Photo Credits: Madison County Emergency Management and Jefferson County Sheriff's Office

A more thorough survey of Debby's forecast history and impacts across a broader region will be available by viewing the National Hurricane Center's Tropical Cyclone Report. These are typically completed several months after a storm has made landfall. It will be available at this link when it's completed.