10:00 pm Sally Update: Forecast Track Shifts a Little More to the East

| September 15, 2020 @ 10:01 pm

SUMMARY OF 1000 PM CDT…0300 UTC…INFORMATION
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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
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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

DISCUSSION AND OUTLOOK
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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
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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
* The 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
* The 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.

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.

Category: Alabama's Weather, ALL POSTS, Severe Weather, Tropical

About the Author ()

Scott Martin is an operational meteorologist, professional graphic artist, musician, husband, and father. Not only is Scott a member of the National Weather Association, but he is also the Central Alabama Chapter of the NWA president. Scott is also the co-founder of Racecast Weather, which provides forecasts for many racing series across the USA. He also supplies forecasts for the BassMaster Elite Series events including the BassMaster Classic.

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