Isaias

000
WTNT34 KNHC 071753
TCPAT4
 
BULLETIN
Tropical Storm Isaias Intermediate Advisory Number 4A
NWS National Hurricane Center Miami FL       AL092026
100 PM CDT Wed Oct 07 2026
 
...NOAA HURRICANE HUNTERS FIND ISAIAS GATHERING STRENGTH...
 
 
SUMMARY OF 100 PM CDT...1800 UTC...INFORMATION
----------------------------------------------
LOCATION...22.6N 93.4W
ABOUT 255 MI...410 KM WNW OF PROGRESO MEXICO
ABOUT 520 MI...840 KM SSW OF THE MOUTH OF THE MISSISSIPPI RIVER
MAXIMUM SUSTAINED WINDS...50 MPH...85 KM/H
PRESENT MOVEMENT...ENE OR 70 DEGREES AT 8 MPH...13 KM/H
MINIMUM CENTRAL PRESSURE...997 MB...29.44 INCHES
 
 
WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:
 
None
 
SUMMARY OF WATCHES AND WARNINGS IN EFFECT:
 
A Storm Surge Watch is in effect for...
* Mouth of the Mississippi River to Yankeetown
 
A Hurricane Watch is in effect for...
* Bay St. Louis to Indian Pass
 
A Tropical Storm Watch is in effect for...
* Jefferson/Plaquemines Parish line to west of Bay St. Louis
* East of Indian Pass to Aucilla River
 
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.
 
A Hurricane Watch means that hurricane conditions are possible
within the watch area.  A watch is typically issued 48 hours
before the anticipated first occurrence of tropical-storm-force
winds, conditions that make outside preparations difficult or
dangerous.
 
A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.
 
Interests in the Yucatan Peninsula of Mexico and elsewhere
around the U.S. northern Gulf Coast should closely monitor the
progress of this system.
 
Additional watches and warnings could be required for a portion of
the U.S. northern Gulf coast later today.
 
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 100 PM CDT (1800 UTC), the center of Tropical Storm Isaias was
located by the NOAA Hurricane Hunters near latitude 22.6 North, 
longitude 93.4 West. Isaias is moving toward the east-northeast 
near 8 mph (13 km/h). A continued east-northeastward motion is 
expected today, followed by a turn toward the northeast and north 
on Thursday and Friday. On the forecast track, Isaias is expected 
to pass to the north of the Yucatan Peninsula on Thursday and 
approach the U.S. northern Gulf Coast on Friday.
 
Maximum sustained winds have increased to near 50 mph (85 km/h) 
with higher gusts. Some strengthening is forecast during the next 
48 hours, and Isaias is forecast to become a hurricane on Thursday.
 
Tropical-storm-force winds extend outward up to 45 miles (75 km)
from the center.
 
The estimated minimum central pressure is 997 mb (29.44 inches) 
based on NOAA dropsonde data.
 
 
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
Mouth of the Mississippi River, LA to Ocean Springs, MS...3-5 ft
Indian Pass, FL to Aucilla River, FL...3-5 ft
Aucilla River, FL to Yankeetown, FL...2-4 ft
Lake Pontchartrain...1-3 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 could begin in the Hurricane Watch area
late Friday, and tropical storm conditions could begin in the
watches areas midday Friday.
 
Gusty winds are possible in portions of the Yucatan Peninsula
on Thursday.
 
RAINFALL: Tropical Storm Isaias is expected to produce rainfall
amounts of 2 to 4 inches through Thursday across coastal portions of
the Bay of Campeche with isolated higher amounts possible in the
states of Campeche and western Yucatan.
 
From Friday through the weekend, the system is expected to produce
rainfall amounts of 3 to 6 inches, with localized totals up to 10
inches, across the central U.S. Gulf Coast extending from far
southeastern Louisiana to the Florida Panhandle. 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, along with isolated
river flooding, will be possible.
 
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
 
SURF: Swells are expected to affect the western and northern
portions of the Yucatan Peninsula beginning on Thursday and spread
northward toward the Gulf Coast late this week. 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 complete advisory at 400 PM CDT.
 
$$
Forecaster Blake