Isaias, advisory 10

000
WTNT34 KNHC 090249
TCPAT4
 
BULLETIN
Hurricane Isaias Advisory Number  10
NWS National Hurricane Center Miami FL       AL092026
1000 PM CDT Thu Oct 08 2026
 
...ISAIAS EXPECTED TO APPROACH THE NORTHERN GULF COAST AS A
DANGEROUS HURRICANE ON FRIDAY...
...STORM SURGE AND HURRICANE WARNINGS REMAIN IN EFFECT...
 
 
SUMMARY OF 1000 PM CDT...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...25.4N 88.4W
ABOUT 295 MI...475 KM NNE OF PROGRESO MEXICO
ABOUT 260 MI...415 KM S OF THE MOUTH OF THE MISSISSIPPI RIVER
MAXIMUM SUSTAINED WINDS...105 MPH...165 KM/H
PRESENT MOVEMENT...NE OR 40 DEGREES AT 14 MPH...22 KM/H
MINIMUM CENTRAL PRESSURE...969 MB...28.62 INCHES
 
 
WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:
 
None.
 
SUMMARY OF WATCHES AND WARNINGS IN EFFECT:
 
A Storm Surge Warning is in effect for...
* Mouth of the Mississippi River to the Suwannee River
 
A Hurricane Warning is in effect for...
* Ocean Springs, MS to the Bay/Gulf County Line, FL
 
A Tropical Storm Warning is in effect for...
* Jefferson/Plaquemines Parish Line, LA to west of Ocean Springs, MS
* East of Bay/Gulf County Line to Aucilla River, FL
 
A Storm Surge Watch is in effect for...
* Suwannee River to Yankeetown, FL
 
A Storm Surge Warning means there is a danger of life-threatening
inundation, from rising water moving inland from the coastline,
during the next 36 hours in the indicated locations. For a depiction
of areas at risk, please see the National Weather Service Storm
Surge Watch/Warning Graphic, available at hurricanes.gov. This is a
life-threatening situation. Persons located within these areas
should take all necessary actions to protect life and property from
rising water and the potential for other dangerous conditions.
Promptly follow evacuation and other instructions from local
officials.
 
A Hurricane Warning means that hurricane conditions are expected
somewhere within the warning area, in this case within 24 to 36
hours. Preparations to protect life and property should be rushed to
completion.
 
A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area within 36 hours.
 
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. For
a depiction of areas at risk, please see the National Weather
Service Storm Surge Watch/Warning Graphic, available at
hurricanes.gov.
 
For storm information specific to your area, including possible
inland watches and warnings, please monitor products issued by your
local National Weather Service forecast office.
 
 
DISCUSSION AND OUTLOOK
----------------------
At 1000 PM CDT (0300 UTC), the center of Hurricane Isaias was 
located near latitude 25.4 North, longitude 88.4 West. Isaias is 
moving toward the northeast near 14 mph (22 km/h). A turn toward the 
north is expected on Friday. On the forecast track, Isaias is 
expected to approach the U.S. northern Gulf Coast on Friday and make 
landfall within the warning area late Friday or early Saturday.
 
Maximum sustained winds have increased to near 105 mph (165 km/h) 
with higher gusts. Isaias could briefly become a major hurricane 
early Friday. Although some weakening is forecast thereafter, Isaias 
will remain a dangerous hurricane as it approaches the northern Gulf 
Coast late Friday.
 
Hurricane-force winds extend outward up to 25 miles (35 km) from the 
center and tropical-storm-force winds extend outward up to 125 miles 
(205 km). NOAA buoy 42001 in the central Gulf recently reported 
sustained winds of 45 mph (72 km/h) and a gust of 56 mph (90 km/h).
 
The estimated minimum central pressure is 969 mb (28.62 inches).
 
 
HAZARDS AFFECTING LAND
----------------------
Key messages for Isaias can be found in the Tropical Cyclone
Discussion under AWIPS header MIATCDAT4 and WMO header WTNT44 KNHC.
 
STORM SURGE: The combination of a dangerous storm surge and the
tide will cause normally dry areas near the coast to be flooded by
rising waters moving inland from the shoreline. The water could
reach the following heights above ground somewhere in the indicated
areas if the peak surge occurs at the time of high tide...
 
Dauphin Island, AL to Indian Pass, FL...5-7 ft
Indian Pass, FL to Steinhatchee River, FL...4-6 ft
Ocean Springs, MS to Dauphin Island, AL...4-6 ft
Mobile Bay...4-6 ft
Mouth of the Mississippi River, LA to Ocean Springs, MS...3-5 ft
Steinhatchee River, FL to Suwannee River, FL...3-5 ft
Suwannee River, FL to Yankeetown, FL...2-4 ft
Yankeetown, FL to Egmont Key, FL...1-3 ft
Lake Pontchartrain...1-3 ft
Morgan City, LA to Mouth of the Mississippi River, LA...1-2 ft
 
The deepest water will occur along the immediate coast in areas of
onshore winds, where the surge will be accompanied by large and
dangerous waves. Surge-related flooding depends on the relative
timing of the surge and the tidal cycle, and can vary greatly over
short distances. For information specific to your area, please see
products issued by your local National Weather Service forecast
office.
 
For a complete depiction of areas at risk of storm surge inundation,
please see the National Weather Service Peak Storm Surge Graphic,
available at hurricanes.gov/graphics_at4.shtml?peakSurge.
 
WIND: Hurricane conditions are expected within the Hurricane Warning
area Friday night into early Saturday, with tropical storm
conditions beginning on Friday. Tropical storm conditions are
expected in the warning areas on Friday and Friday night.
 
RAINFALL: From Friday through the weekend, Isaias is expected to
produce rainfall amounts of 4 to 8 inches across southern Alabama,
the Florida Panhandle and Big Bend, and southwest Georgia. Localized
totals up to 15 inches are possible, particularly within banding
across the Florida Panhandle and Big Bend. Across the coastal
Carolinas, rainfall of 3 to 5 inches, with localized totals up to 8
inches are possible. Rainfall amounts of 1 to 3 inches, with
localized amounts up to 5 inches, are possible across much of the
remainder of the Southeast. Flash and urban flooding is likely
across the region, with considerable impacts possible across much of
southern Alabama and the Florida Panhandle into southwestern
Georgia. River flooding is also expected, some of which could be
significant.
 
For a complete depiction of forecast rainfall associated with
Isaias, please see the National Weather Service Storm Total Rainfall
Graphic available at hurricanes.gov/graphics_at4.shtml?rainqpf and
the Flash Flood Risk graphic at
hurricanes.gov/graphics_at4.shtml?ero.
 
TORNADOES: A risk for tornadoes will begin Friday evening in coastal
areas of Alabama, the Florida Panhandle, and far southwest Georgia.
The tornado threat will continue through Saturday for parts of
eastern Alabama into Georgia and the Florida Panhandle.
 
SURF: Swells from Isaias are affecting the western and northern
portions of the Yucatan Peninsula and will spread northward toward
the Gulf Coast on Friday. These swells are likely to cause
life-threatening surf and rip current conditions. Please consult
products from your local weather office.
 
A depiction of rip current risk for the United States can be found
at: hurricanes.gov/graphics_at4.shtml?ripCurrents
 
 
NEXT ADVISORY
-------------
Next intermediate advisory at 100 AM CDT.
Next complete advisory at 400 AM CDT.
 
$$
Forecaster Reinhart
 

000
WTNT44 KNHC 090250
TCDAT4
 
Hurricane Isaias Discussion Number  10
NWS National Hurricane Center Miami FL       AL092026
1000 PM CDT Thu Oct 08 2026
 
The satellite presentation of Isaias has improved over the past few 
hours. Infrared cloud top temperatures have cooled within the 
expanding central dense overcast, and recent images show a warm spot 
that could be an emerging eye. A series of earlier passive microwave 
images showed the mid-level eyewall was open to the southwest, and a 
comparison of the AMSR3 89- and 37-GHz channels indicated the vortex 
was slightly tilted with height due to continued southwesterly 
shear. The stronger Tail Doppler Radar winds noted from the previous 
mission indicated the satellite intensity estimates are likely 
running too low, and based on the improved structure of the 
hurricane, the initial intensity is raised to 90 kt. Air Force and 
NOAA Hurricane Hunter aircraft are scheduled to collect data in 
Isaias overnight.

Isaias is moving toward the northeast (040/12 kt), but is expected 
to turn northward and accelerate on Friday within the flow between 
an upper trough near the northwestern Gulf Coast and a subtropical 
ridge extending across the western Atlantic. Landfall is expected to 
occur within the hurricane warning area Friday night or early 
Saturday, with the updated 24-h forecast near the coast. The NHC 
forecast continues to lie closer to the right side of the guidance 
envelope, very near the latest corrected consensus (HCCA). This 
results in little overall change from the previous prediction, 
although this forecast is slightly faster based on the model trends 
this cycle.

High oceanic heat content and strong upper-level divergence could 
allow for additional strengthening overnight while the shear vector 
is still oriented in the direction of storm motion. A majority of 
Google DeepMind ensemble members show Isaias briefly reaching major 
hurricane status early Friday (along with some of the hurricane 
regional models), and this is now reflected in the NHC forecast. 
This strengthening should be short lived as southwesterly shear from 
the aforementioned trough will increase considerably on Friday and 
cause some weakening before landfall. Nonetheless, Isaias will be a 
dangerous hurricane with significant storm surge, damaging winds, 
and flooding rains when it reaches the northern Gulf Coast. During 
this time, the wind field is also predicted to grow due to the 
trough interaction, and some of these impacts will extend well away 
from the center. After landfall, gusty winds are expected to reach 
well inland over portions of the southeastern United States.

 
Key Messages:
 
1. A life-threatening storm surge is expected from the Mouth of the
Mississippi River to Suwannee, Florida. Residents in the warning
area should follow advice given by local officials and evacuate
immediately if told to do so.
 
2. Damaging hurricane force-winds are expected over portions of the
Florida Panhandle, southern Alabama, and southern Mississippi where
a Hurricane Warning is in effect. Residents in these areas should
prepare for the possibility of long-duration power outages.
 
3. Damaging wind gusts are possible over much of central and 
northern Alabama, extreme eastern Mississippi, and portions of 
western and northern Georgia, especially in areas of higher terrain. 
Additional Tropical Storm and High Wind Watches and Warnings may be 
required for portions of that area later tonight or on Friday. 
Residents should secure loose outdoor items, avoid driving 
high-profile vehicles, and prepare for power outages.
 
4. Isaias will bring areas of heavy rainfall to the central U.S. 
Gulf Coast and much of the Southeast Friday into the weekend. 
Considerable flash and urban flooding, along with significant river 
flooding, will be possible.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  09/0300Z 25.4N  88.4W   90 KT 105 MPH
 12H  09/1200Z 27.1N  87.6W  100 KT 115 MPH
 24H  10/0000Z 29.9N  87.1W   85 KT 100 MPH
 36H  10/1200Z 32.2N  87.3W   45 KT  50 MPH...INLAND
 48H  11/0000Z 34.1N  87.5W   30 KT  35 MPH...POST-TROP/INLAND
 60H  11/1200Z 36.1N  86.1W   20 KT  25 MPH...POST-TROP/INLAND
 72H  12/0000Z 38.0N  83.0W   20 KT  25 MPH...POST-TROP/INLAND
 96H  13/0000Z...DISSIPATED
 
$$
Forecaster Reinhart