Isaias, advisory 8

000
WTNT34 KNHC 081456
TCPAT4
 
BULLETIN
Hurricane Isaias Advisory Number   8
NWS National Hurricane Center Miami FL       AL092026
1000 AM CDT Thu Oct 08 2026
 
...ISAIAS STRONGER...
...PREPARATIONS TO PROTECT LIFE AND PROPERTY FROM STORM SURGE AND
DAMAGING WINDS IN THE WARNING AREA SHOULD BE RUSHED TO COMPLETION 
TODAY...
 
 
SUMMARY OF 1000 AM CDT...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...23.7N 90.2W
ABOUT 170 MI...270 KM N OF PROGRESO MEXICO
ABOUT 380 MI...610 KM S OF THE MOUTH OF THE MISSISSIPPI RIVER
MAXIMUM SUSTAINED WINDS...85 MPH...140 KM/H
PRESENT MOVEMENT...ENE OR 60 DEGREES AT 10 MPH...17 KM/H
MINIMUM CENTRAL PRESSURE...975 MB...28.80 INCHES
 
 
WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:
 
A Storm Surge Warning has been issued from the Steinhatchee River
eastward to the Suwannee River, Florida.
 
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
 
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. A warning is typically issued 36
hours before the anticipated first occurrence of
tropical-storm-force winds, conditions that make outside
preparations difficult or dangerous. 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.
 
Interests in the Yucatan Peninsula of Mexico and elsewhere along the
U.S. northern Gulf Coast should closely monitor the progress of this
system.
 
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 AM CDT (1500 UTC), the center of Hurricane Isaias was
located near latitude 23.7 North, longitude 90.2 West. Isaias is
moving toward the east-northeast near 10 mph (17 km/h).  A turn
toward the northeast is expected later today followed by a turn
northward on Friday. On the forecast track, Isaias is expected to
pass to the north of the Yucatan Peninsula later today and make
landfall along the U.S. northern Gulf Coast within the warning area
late Friday or early Saturday.
 
Maximum sustained winds have increased to near 85 mph (140 km/h) 
with higher gusts.  Additional strengthening is expected through 
early Friday, and Isaias should remain a dangerous hurricane as it 
approaches the northern Gulf Coast Friday night.
 
Hurricane-force winds extend outward up to 15 miles (30 km) from the
center and tropical-storm-force winds extend outward up to 90 miles
(150 km).
 
The estimated minimum central pressure is 975 mb (28.80 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...
 
Ocean Springs, MS to Indian Pass, FL...5-7 ft
Mobile Bay...5-7 ft
Indian Pass, FL to Steinhatchee River, FL...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
 
The deepest water will occur along the immediate coast near and to
the east of the landfall location, 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.
 
Gusty winds are possible in portions of the Yucatan Peninsula today.
 
RAINFALL: Isaias is expected to produce rainfall amounts of 1 to 3 
inches through Thursday across coastal portions of the eastern Bay 
of Campeche with isolated higher amounts possible in the states of 
Campeche and western Yucatan.

From Friday through the weekend, Isaias is expected to produce 
rainfall amounts of 3 to 7 inches across the central U.S. Gulf Coast 
extending from far southeastern Louisiana to the Florida Big Bend 
region. Localized totals up to 15 inches are possible, particularly 
within banding across the Florida Panhandle and Big Bend. Rainfall 
amounts of 1 to 3 inches, with localized amounts up to 5 inches, are 
possible across much of the Southeast as far north as the Tennessee 
Valley and the Carolinas. Flash and urban flooding is possible 
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 
Tropical Storm 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: Isolated tornadoes will be possible Friday night in
coastal areas of Alabama and the Florida Panhandle and far
southwestern Georgia. The tornado threat will continue Saturday for
eastern Alabama, Georgia and northern Florida.
 
SURF: Swells will affect the western and northern portions of the
Yucatan Peninsula beginning later today and 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 PM CDT.
Next complete advisory at 400 PM CDT.
 
$$
Forecaster Pasch
 

000
WTNT44 KNHC 081457
TCDAT4
 
Hurricane Isaias Discussion Number   8
NWS National Hurricane Center Miami FL       AL092026
1000 AM CDT Thu Oct 08 2026

Isaias is strengthening in an environment of moderate vertical wind 
shear.  Observations from an Air Force Hurricane Hunter aircraft 
indicate that the central pressure continues to fall and the 
maximum winds are now near 75 kt.  The center of the hurricane is 
near the southwestern side of a Central Dense Overcast feature, and 
some convective banding features are evident over the eastern 
portion of the circulation.  Additional aircraft reconnaissance 
missions are scheduled for today, tonight, and Friday, so we will 
have close monitoring of the intensity of the system up until 
landfall.

Center fixes from the Hurricane Hunters indicate that Isais 
continues on a generally east-northward track with an initial 
motion of about 060/9 kt.  During the next 36 hours, the hurricane 
should gradually turn toward the northeast and north as it moves 
between a ridge extending from the Bahamas across the Florida 
Peninsula and a zonally-oriented mid-level trough near the 
northwestern Gulf coast.  On the forecast track, the center of the 
hurricane is forecast to move across the east-central to 
northeastern Gulf coast in 36-42 hours.  Thereafter, the weakening 
cyclone should move over the southeastern United States bringing 
strong winds well inland.  The track guidance has not changed much 
for this advisory cycle and the official forecast is similar to that 
of the previous advisory.

The intensity forecast up to landfall is somewhat challenging.  
On the one hand, the hurricane should move over waters of high 
oceanic heat content and within a fairly moist air mass through 
tomorrow.  On the other hand, the SHIPS model input parameters show 
a significant increase in vertical wind shear, particularly when 
Isais nears the coast.  Regarding, the shorter-term intensity 
forecast, a recent WSFM microwave satellite image at 37 GHz 
frequency shows a closed ring around the eye.  This is typically a 
harbinger of rapid intensification.  The 12-hour forecast does show 
a relatively large increase in strength, but in view of the 
expected stronger shear in 24-36 hours, some decrease in intensity 
is indicated as Isaias approaches the coast.  Regardless, Isaias is 
expected to remain a dangerous hurricane through landfall, and 
gusty winds are expected well inland after landfall given the 
anticipated expansion of the wind field and accelerating forward 
speed of the storm.
 
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 and portions of western and northern Georgia, 
especially in areas of higher terrain.  Additional Tropical Storm 
and High Wind Watches and Warnings will likely be required for 
portions of that area later today. 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.

5. Isaias could bring gusty winds and areas of heavy rain to the 
western portion of the Yucatan Peninsula today.


FORECAST POSITIONS AND MAX WINDS
 
INIT  08/1500Z 23.7N  90.2W   75 KT  85 MPH
 12H  09/0000Z 24.9N  89.0W   90 KT 105 MPH
 24H  09/1200Z 27.1N  87.9W   95 KT 110 MPH
 36H  10/0000Z 29.6N  87.4W   85 KT 100 MPH
 48H  10/1200Z 32.3N  87.8W   35 KT  40 MPH...INLAND
 60H  11/0000Z 34.6N  88.1W   30 KT  35 MPH...POST-TROP/INLAND
 72H  11/1200Z 36.5N  87.8W   25 KT  30 MPH...POST-TROP/INLAND
 96H  12/1200Z...DISSIPATED
 
$$
Forecaster Pasch