Advisories

000
WTNT44 KNHC 080253
TCDAT4
 
Tropical Storm Isaias Discussion Number   6
NWS National Hurricane Center Miami FL       AL092026
1000 PM CDT Wed Oct 07 2026
 
Aircraft data and satellite trends indicate Isaias has continued 
intensifying this evening. The center of the tropical cyclone is 
embedded underneath a small central dense overcast with very cold 
tops associated with deep convection. Upper-level outflow is 
observed in all quadrants, though it remains somewhat restricted to 
the southwest due to moderate vertical wind shear. Data from the Air 
Force Hurricane Hunters indicates the central pressure has fallen to 
988 mb, and on the last fix they reported a circular eyewall open to 
the southwest. Based on these developments, the initial intensity is 
raised to 60 kt.

Aircraft fixes indicate the center is still moving toward the 
east-northeast (070/8 kt). The system is expected to accelerate 
northeastward tomorrow and then northward on Friday within the flow 
between a deepening trough over the south-central United States and 
a strengthening subtropical ridge over the western Atlantic. This 
steering pattern is forecast to bring the center of Isaias to the 
northern Gulf Coast late Friday night into early Saturday. There 
were no major changes to the guidance suite, with the AI-based 
models generally faster and farther right than the physics-based 
models. The NHC forecast continues to lean more heavily on the 
better-performing corrected consensus (HCCA) and Google DeepMind 
(GDMI) aids, remaining on the faster and right side of the guidance 
envelope. The inland track at 60-72 h was shifted westward as more 
models now show Isaias becoming captured by the cutoff low over the 
southeastern United States.

Continued strengthening is expected during the next day or so as 
Isaias moves over very warm waters in a moist environment with 
moderate vertical wind shear. Given its small size and formative 
inner core, rapid intensification is a distinct possibility, and the 
NHC forecast lies on the high end of the intensity guidance. The 
shear is predicted to markedly increase on Friday while Isaias 
approaches the northern Gulf Coast, but the system is expected to 
remain a dangerous hurricane through landfall. Gusty winds are 
expected well inland after landfall given the anticipated expansion 
of the wind field and fast forward speed of the storm.

Hurricane, Storm Surge, and Tropical Storm Warnings have been 
issued with this advisory for portions of the northern Gulf Coast.

 
Key Messages:
 
1. Isaias is expected to strengthen and be a strong hurricane when 
it approaches the northern Gulf Coast on Friday. A life-threatening 
storm surge is expected along a portion of the northern Gulf Coast, 
and a Storm Surge Warning is now in effect from the Mouth of the 
Mississippi River to Steinhatchee, Florida. Residents in the warning 
area should follow advice given by local officials and evacuate if 
told to do so.
 
2. Damaging hurricane force-winds are expected over portions of the 
Florida Panhandle, southern Alabama, and southern Mississippi, and a 
Hurricane Warning is now in effect from Ocean Springs, Mississippi 
to the Bay/Gulf County Line, Florida. Residents in these areas 
should prepare for the possibility of long-duration power outages. 
 
3. Isaias will bring areas of heavy rainfall to the central U.S. 
Gulf coast and much of the Southeast Friday into the weekend. Flash 
and urban flooding, along with isolated river flooding, will be 
possible.
 
4. Isaias could bring gusty winds and areas of heavy rain to the 
western portion of the Yucatan Peninsula through Thursday.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  08/0300Z 22.9N  91.9W   60 KT  70 MPH
 12H  08/1200Z 23.4N  90.7W   75 KT  85 MPH
 24H  09/0000Z 24.7N  89.1W   85 KT 100 MPH
 36H  09/1200Z 26.8N  87.9W   95 KT 110 MPH
 48H  10/0000Z 29.6N  87.3W   90 KT 105 MPH
 60H  10/1200Z 32.5N  87.5W   50 KT  60 MPH...INLAND
 72H  11/0000Z 35.1N  88.0W   25 KT  30 MPH...POST-TROP/INLAND
 96H  12/0000Z...DISSIPATED
 
$$
Forecaster Reinhart