Official Discussion issued by the National Hurricane Center

Debby (AL042024) DATA RELEASED: 8/5/2024 9:00:00 PM UTC

Copy of official data

Tropical Storm Debby Discussion Number  14
NWS National Hurricane Center Miami FL       AL042024
500 PM EDT Mon Aug 05 2024

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.  Assuming a continued weakening since 
landfall, the intensity estimate has been reduced to 45 kt, which is 
reasonably consistent with the latest WSR-88D radar velocities 
aloft.

Debby continues to move through a weakness in the subtropical high, 
and the forward motion has slowed to about 035/6 kt.  The cyclone 
is expected to turn eastward, while moving quite slowly, in a 
region of weak steering currents for the next couple of days.  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 
forecast period.  The NHC track forecast is similar to the previous 
one and is in good agreement with the corrected model consensus, 
HCCA, guidance.

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 this may be 
conservative.

Given the sluggish forward motion of Debby, extremely large amounts 
of rainfall over the Southeastern U.S. is anticipated.

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.


FORECAST POSITIONS AND MAX WINDS

INIT  05/2100Z 30.5N  82.9W   45 KT  50 MPH
12H  06/0600Z 31.2N  82.1W   35 KT  40 MPH...INLAND
24H  06/1800Z 31.7N  81.2W   35 KT  40 MPH...INLAND
36H  07/0600Z 31.7N  80.1W   35 KT  40 MPH...OVER WATER
48H  07/1800Z 32.1N  79.2W   40 KT  45 MPH...OVER WATER
60H  08/0600Z 32.6N  79.1W   45 KT  50 MPH...OVER WATER
72H  08/1800Z 33.2N  79.2W   50 KT  60 MPH...INLAND
96H  09/1800Z 35.3N  79.1W   30 KT  35 MPH...INLAND
120H  10/1800Z 38.5N  75.5W   30 KT  35 MPH...INLAND

$$
Forecaster Pasch