During the last week of July, a tropical wave crossed the tropical Atlantic and moved along the northern Caribbean islands. For much of that journey, dry air stifled its development, but by August 1 it was starting to show some more signs of organization. The disturbance passed over Hispaniola and Cuba, bringing heavy rainfall. The land interaction slowed development a bit longer, but the system found a window to consolidate south of central Cuba later on August 2 and was classified Tropical Depression Four. The storm was initially steered west-northwest by a strong subtropical ridge, but a weakness over the eastern U.S. gave it the opportunity to turn northwest on August 3. The center passed over western Cuba that morning.
That evening, the cyclone emerged into the Gulf of Mexico. It found a much more humid atmosphere and low wind shear, which allowed the system to begin strengthening and become Tropical Storm Debby that evening. Thunderstorm activity began to build near the center of circulation early on August 4. Radar imagery also showed an eyewall building throughout the day as Debby paralleled the coastline of western Florida. The storm then turned north-northeast overnight and reached category 1 hurricane strength. It made landfall in the Big Bend of Florida during the morning of August 5 at its peak intensity of 80 mph winds and a central pressure of 979 mb.
Debby entered an area of weak steering currents and slowed down that day as it moved farther inland. Its winds diminished and the inner core decayed that evening as the cyclone was cut off from energy from the ocean. Nevertheless, a severe flooding event began to unfold for the southeast U.S. due to the slow movement of the storm. The center crossed Georgia and emerged over the Atlantic near the Georgia-South Carolina border during the afternoon of August 6. At the time, it was still hanging on to minimal tropical storm intensity. Though it moved over water, the storm did not travel eastward far enough to find the highest oceanic heat content of the region in the Gulf stream. As a result, the circulation remained mostly devoid of convection near the center and only gradually built back outer bands on August 7. It also underwent modest deepening, but did not much resemble a typical tropical storm. A rebuilding ridge to Debby's east began to push it back to the west of north that evening and made landfall in northern South Carolina overnight.
The storm's rains spread northward as it weakened inland on August 8. Late that afternoon, it weakened to a tropical depression. By early the next morning, the system became post-tropical over Virginia. The remnants of Debby sped off to the northeast and brought additional rain to the mid-Atlantic and regions farther north over the next couple of days.
The image above shows Debby at peak intensity as a category 1 hurricane in the early morning hours of August 5, just before Florida landfall.
Debby's slow movement across the U.S. southeast brought large rainfall totals, though flooding impacts were not as severe as initially feared.
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