7 pm Advisory — Ida Continues to Move Further Inland Over Southeastern Louisiana

SUMMARY OF 7 PM CDT INFORMATION
LOCATION…29.9N 90.5W
ABOUT 25 MI…40 KM WSW OF NEW ORLEANS, LOUISIANA
ABOUT 55 MI…85 KM SE OF BATON ROUGE, LOUISIANA
MAXIMUM SUSTAINED WINDS…120 MPH…195 KM/H
PRESENT MOVEMENT…NW OR 325 DEGREES AT 10 MPH…17 KM/H
MINIMUM CENTRAL PRESSURE…944 MB…27.88 INCHES

WATCHES AND WARNINGS
A Storm Surge Warning is in effect for…
* Morgan City, Louisiana, to the Alabama/Florida border
* Lake Borgne, Lake Pontchartrain, Lake Maurepas, and Mobile Bay

A Hurricane Warning is in effect for…
* Morgan City, Louisiana, to the Mouth of the Pearl River
* Lake Pontchartrain, Lake Maurepas, and Metropolitan New Orleans

A Tropical Storm Warning is in effect for…
* Intracoastal City, Louisiana, to the west of Morgan City, Louisiana
* Mouth of the Pearl River to the Alabama/Florida border

FORECAST DISCUSSION
At 700 PM CDT (0000 UTC), the eye of Hurricane Ida was located near latitude 29.9 North, longitude 90.5 West. Ida is moving toward the northwest near 10 mph (17 km/h). A turn toward the north is expected overnight, followed by a slightly faster northeastward motion by Monday night and Tuesday. On the forecast track, the center of Ida will move farther inland over southeastern Louisiana tonight. Ida is then forecast to move well inland over portions of western Mississippi Monday and Monday night, and move across the Tennessee Valley on Tuesday.

Doppler radar data indicate that the maximum sustained winds are near 120 mph (195 km/h) with higher gusts. Ida is a dangerous category 3 hurricane on the Saffir-Simpson Hurricane Wind Scale. Rapid weakening is expected during the next day or so, however, Ida is forecast to remain a hurricane through late tonight and remain a tropical storm until Monday afternoon.

Hurricane-force winds extend outward up to 45 miles (75 km) from the center, and tropical-storm-force winds extend outward up to 150 miles (240 km). A sustained wind of 62 mph (100 km/h) with a gust of 83 mph (133 km/h) was recently observed at New Orleans International Airport. A sustained wind of 62 mph (100 km/h) and a gust of 85 mph (137 km/h) was recently reported at Frenier Landing, Louisiana.

The estimated minimum central pressure is 944 mb (27.88 inches). A Florida Coastal Monitoring Program observing station located northeast of Raceland, Louisiana, recently reported a minimum pressure of 945 mb (27.91).

HAZARDS TO LAND
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…

Morgan City, LA to Bay St. Louis, MS including Lake Borgne…7-11 ft
Lake Pontchartrain…5-8 ft
Bay St. Louis, MS to Ocean Springs, MS…4-7 ft
Lake Maurepas…4-6 ft
Ocean Springs to AL/FL border including Mobile Bay…3-5 ft
Intracoastal City, LA to Morgan City, LA including Vermilion Bay…1-3 ft
AL/FL border to Okaloosa/Walton County Line, including Pensacola Bay…1-3 ft

Overtopping of local levees outside of the Hurricane and Storm Damage Risk Reduction System is possible where local inundation values may be higher than those shown above.

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.

WIND: Catastrophic wind damage is likely near the core of Ida as it moves farther inland over southeastern Louisiana through this evening.

Hurricane conditions will spread farther inland within the Hurricane Warning area over southeastern Louisiana tonight. Tropical storm conditions will also spread inland over portions of Louisiana and Mississippi tonight and Monday.

RAINFALL: Heavy rainfall from Ida will continue to impact the southeast Louisiana coast, spreading northeast into the Lower Mississippi Valley this evening into Monday. Total rainfall
accumulations of 10 to 18 inches, with isolated maximum amounts of 24 inches, are possible across southeast Louisiana into far southern Mississippi through Monday. This is likely to result in life-
threatening flash and urban flooding and significant river flooding impacts.

Ida is forecast to turn to the northeast on Monday and track across the Middle Tennessee Valley and Upper Ohio Valley through Wednesday, producing the following rainfall totals:

Coastal Alabama to the far western Florida panhandle: 5 to 10 inches, with isolated maximum amounts of 15 inches, today through Tuesday morning.

Central Mississippi: 4 to 8 inches, with isolated maximum amounts of 12 inches, tonight through Monday night.

Middle Tennessee Valley, Upper Ohio Valley, Central Appalachians into the Mid-Atlantic: 3 to 6 inches with isolated higher amounts, Tuesday into Wednesday.

These rainfall totals will result in considerable flash flooding, along with widespread minor to isolated major riverine flooding from the Lower Mississippi Valley into far western Alabama.

TORNADOES: Tornadoes will be most likely through Monday over southeast Louisiana, southern Mississippi, southwest Alabama, and the western Florida Panhandle. A few tornadoes are also possible farther north across much of Mississippi and Alabama on Monday.

SURF: Swells will continue to affect the northern Gulf coast through early Monday. These swells are likely to cause life-threatening surf and rip current conditions.

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