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After Landfall, Laura Continues to Cause Catastrophic Storm Surge, Flash Flooding, & Extreme Winds in Portions of Louisiana

| August 27, 2020 @ 1:11 am

SUMMARY OF 100 AM CDT…0600 UTC…INFORMATION
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LOCATION…29.8N 93.3W
ABOUT 30 MI…45 KM SSW OF LAKE CHARLES LOUISIANA
ABOUT 40 MI…70 KM E OF PORT ARTHUR TEXAS
MAXIMUM SUSTAINED WINDS…150 MPH…240 KM/H
PRESENT MOVEMENT…N OR 350 DEGREES AT 15 MPH…24 KM/H
MINIMUM CENTRAL PRESSURE…938 MB…27.70 INCHES

WATCHES AND WARNINGS
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A Storm Surge Warning is in effect for…
* Freeport Texas to the Mouth of the Mississippi River

A Hurricane Warning is in effect for…
* High Island Texas to Intracoastal City Louisiana

A Tropical Storm Warning is in effect for…
* San Luis Pass to High Island Texas
* East of Intracoastal City Louisiana to the Mouth of the Mississippi River

A Hurricane Watch is in effect for…
* East of Intracoastal City to the west of Morgan City Louisiana

DISCUSSION AND OUTLOOK
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At 100 AM CDT (0600 UTC), Doppler radar images indicate that the eye of Hurricane Laura has made landfall at the coast near Cameron, Louisiana, near latitude 29.8 North, longitude 93.3 West. Laura is moving toward the north near 15 mph (24 km/h), and this motion should continue throughout the day. A northeastward to east-northeastward motion is expected tonight and Friday. On the forecast track, Laura will move inland across southwestern Louisiana this morning and then continue northward across the state through this afternoon. The center of Laura is forecast to move over Arkansas tonight, and over the mid-Mississippi Valley on Friday, and the mid-Atlantic states on Saturday.

Air Force reconnaissance and Doppler radar data indicate that the maximum sustained winds are near 150 mph (240 km/h) with higher gusts. Rapid weakening is forecast as Laura moves inland.

Hurricane-force winds extend outward up to 60 miles (95 km) from the center and tropical-storm-force winds extend outward up to 205 miles (335 km). A Weatherflow site in Cameron recently reported a sustained wind of 101 mph (163 km/h) with a gust to 116 mph (187 km/h). A National Ocean Service site at Calcasieu Pass reported a sustained wind of 93 mph (150 km/h) and a wind gust of 127 mph (204 km/h) within the last hour. A wind gust of 104 mph (167 km/h) was recently reported at Lake Charles, Louisiana.

The minimum central pressure estimated from Air Force Hurricane Hunter observations are 938 MB (27.70 inches).

HAZARDS AFFECTING LAND
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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…

Johnson Bayou to Rockefeller Wildlife Refuge including Calcasieu Lake…15-20 ft
Rockefeller Wildlife Refuge to Intracoastal City…10-15 ft
Intracoastal City to Morgan City including Vermilion Bay…8-12 ft
Sea Rim State Park to Johnson Bayou including Sabine Lake…6-9 ft
Morgan City to Mouth of the Mississippi River…4-7 ft
High Island to Sea Rim State Park…3-6 ft
Freeport to High Island including Galveston Bay…2-4 ft
Mouth of the Mississippi River to Ocean Springs including Lake Borgne…1-3 ft
Lake Pontchartrain and Lake Maurepas…1-3 ft

The deepest water will occur along the immediate coast near and to the right of the landfall location, where the surge will be accompanied by large and destructive waves.

Unsurvivable storm surge with large and destructive waves will cause catastrophic damage from Sea Rim State Park, Texas, to Intracoastal City, Louisiana, including Calcasieu and Sabine Lakes. This surge could penetrate up to 40 miles inland from the immediate coastline, and flood waters will not fully recede for several days after the storm.

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 in the hurricane warning area through the morning, with catastrophic wind damage expected near Laura’s eyewall. Tropical storm conditions will spread northward within the warning areas through the day.

Hurricane-force winds and damaging wind gusts are also expected to spread well inland into portions of eastern Texas and western Louisiana this morning.

RAINFALL: Through Friday, Laura is expected to produce the following rainfall totals:

Across the northwestern Gulf Coast from far southwest Louisiana and the Golden Triangle of Southeast Texas: 8 to 12 inches with isolated totals of 18 inches.

Across central and the rest of western Louisiana into far eastern Texas: 5 to 10 inches with isolated totals of 15 inches.

Across much of Arkansas: 3 to 7 inches with isolated totals of 10 inches.

This rainfall will cause widespread flash and urban flooding, small streams and creeks to overflow their banks, and minor to moderate freshwater river flooding.

By Friday into Saturday, Laura is expected to produce the following rainfall totals:

Across the mid-Mississippi and portions of the Tennessee Valley, Lower Ohio Valley, and central Appalachians: 2 to 4 inches with isolated maximum amounts of 6 inches.

This rainfall may lead to flash and urban flooding and rapid rises on small streams.

Across the Mid-Atlantic Region: 1 to 3 inches.

TORNADOES: Several tornadoes are expected overnight over Louisiana, far southeast Texas, and southwestern Mississippi. The risk for tornadoes will continue through the day across Louisiana, Arkansas, and western Mississippi.

SURF: Swells produced by Laura are affecting the U.S. Gulf coast from the west coast of Florida to Texas and northeastern Mexico. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office.

Category: 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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