Hurricane Sally Advisory # 19

BULLETIN
Hurricane Sally Advisory Number  19
NWS National Hurricane Center Miami FL       AL192020
1000 PM CDT Tue Sep 15 2020

...HURRICANE CONDITIONS EXPECTED TO REACH PORTIONS OF THE
NORTH-CENTRAL GULF COAST LATE TONIGHT AND EARLY WEDNESDAY...
...HISTORIC LIFE-THREATENING FLOODING LIKELY ALONG PORTIONS
OF THE NORTHERN GULF COAST...


SUMMARY OF 1000 PM CDT...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...29.8N 87.8W
ABOUT 65 MI...105 KM SSE OF MOBILE ALABAMA
ABOUT 60 MI...95 KM SW OF PENSACOLA FLORIDA
MAXIMUM SUSTAINED WINDS...85 MPH...140 KM/H
PRESENT MOVEMENT...NNE OR 20 DEGREES AT 2 MPH...4 KM/H
MINIMUM CENTRAL PRESSURE...972 MB...28.71 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

The Storm Surge Warning has been extended east of the
Okaloosa/Walton County Line to the Walton/Bay County Line Florida.

The Hurricane Warning has been extended east of Navarre Florida to
the Okaloosa/Walton County line Florida.

The Storm Surge Warning has been discontinued between the Mouth of
the Pearl River and the Mississippi/Alabama border.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Warning is in effect for...
* Mississippi/Alabama border to the Walton/Bay County Line Florida
* Mobile Bay
* Mouth of the Mississippi River to the Mouth of the Pearl River

A Hurricane Warning is in effect for...
* East of Bay St. Louis Mississippi to the Okaloosa/Walton County
line Florida

A Tropical Storm Warning is in effect for...
* East of the Okaloosa/Walton County line Florida to Indian Pass
Florida
* Bay St. Louis Mississippi westward to Grand Isle Louisiana

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.  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.

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 Sally was located
near latitude 29.8 North, longitude 87.8 West.  Sally is moving 
toward the north-northeast near 2 mph (4 km/h).  A 
north-northeastward to northeastward motion at a slightly faster 
forward speed is expected on Wednesday and Wednesday night, followed 
by a faster northeastward motion on Thursday.  On the forecast 
track, the center of Sally will approach the northern Gulf Coast 
tonight, and make landfall in the hurricane warning area early 
Wednesday.  Sally is expected to move inland across southeastern 
Alabama Wednesday night and Thursday.

Maximum sustained winds are near 85 mph (140 km/h) with higher
gusts.  Some strengthening is possible before landfall, and Sally
is expected to be a dangerous hurricane when it moves onshore along
the north-central Gulf Coast.

Hurricane-force winds extend outward up to 40 miles (65 km) from the
center and tropical-storm-force winds extend outward up to 125 miles
(205 km).

The minimum central pressure reported by the Hurricane Hunters is
972 mb (28.71 inches).


HAZARDS AFFECTING LAND
----------------------
Key messages for Sally can be found in the Tropical Cyclone
Discussion under AWIPS header MIATCDAT4 and WMO header WTNT44 KNHC,
and on the web at www.hurricanes.gov/text/MIATCDAT4.shtml

RAINFALL:  Sally is forecast to produce 10 to 20 inches of rainfall
with isolated amounts of 30 inches along and just inland of the
central Gulf Coast from the Florida Panhandle west of the
Apalachicola River to the Alabama/Mississippi border.  Historic,
life-threatening flash flooding is likely.  In addition, this
rainfall will lead to widespread moderate to major flooding on
area rivers.

Sally is forecast to turn inland Wednesday and track across the
Southeast producing rainfall of 4 to 8 inches, with isolated maximum
amounts of 12 inches, across portions of southeastern Mississippi,
southern and central Alabama, central and northern Georgia, and the
western Carolinas.  Significant flash and urban flooding is likely,
as well as widespread minor to moderate flooding on some rivers.

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 Okaloosa/Walton County FL Line...4-6 ft
Pensacola Bay and Choctawhatchee Bay FL...4-6 ft
Mobile Bay...3-5 ft 
Okaloosa/Walton County Line to Walton/Bay County line FL...2-4 ft
Mouth of the Mississippi River to Mouth of the Pearl River including 
Lakes Pontchartrain, Maurepas and Borgne...2-4 ft
MS/AL Border to Dauphin Island AL...2-4 ft
Walton/Bay County line to Chassahowitzka FL including Saint Andrew 
Bay...1-3 ft
Mouth of the Pearl River to MS/AL Border...1-3 ft

The deepest water will occur along the immediate coast in areas of
onshore winds, where the surge will be accompanied by large and
damaging 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.

WIND:  Hurricane conditions are expected to begin within the
hurricane warning area later tonight.  Tropical storm conditions are
already occurring in portions of the warning areas, and will 
continue through Wednesday night.

TORNADOES:  A few tornadoes may occur through Wednesday across
portions of the Florida Panhandle and southern Alabama.

SURF:  Swells from Sally will continue to affect the coast from the
Florida Big Bend westward to southeastern Louisiana during the next
couple of days. These swells are likely to cause life-threatening
surf and rip current conditions.  Please consult products from your
local weather office.

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