Delta Intermediate Advisory # 21A

BULLETIN
Hurricane Delta Intermediate Advisory Number 21A
NWS National Hurricane Center Miami FL       AL262020
700 PM CDT Fri Oct 09 2020

...DELTA JUST INLAND ALONG THE SOUTHWESTERN LOUISIANA COAST...
...HURRICANE CONDITIONS AND A LIFE-THREATENING STORM SURGE
OCCURRING WITHIN THE WARNING AREA...


SUMMARY OF 700 PM CDT...0000 UTC...INFORMATION
----------------------------------------------
LOCATION...30.0N 93.0W
ABOUT 25 MI...40 KM WSW OF JENNINGS LOUISIANA
MAXIMUM SUSTAINED WINDS...90 MPH...150 KM/H
PRESENT MOVEMENT...NNE OR 15 DEGREES AT 14 MPH...22 KM/H
MINIMUM CENTRAL PRESSURE...971 MB...28.67 INCHES


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

The Storm Surge Warning from High Island, Texas to Sabine Pass has
been discontinued.

The Tropical Storm Warning west of San Luis Pass, Texas has been
discontinued.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Warning is in effect for...
* East of Sabine Pass to the Mouth of the Pearl River including
Calcasieu Lake, Vermilion Bay, and Lake Borgne

A Hurricane Warning is in effect for...
* High Island Texas to Morgan City Louisiana

A Tropical Storm Warning is in effect for...
* West of High Island to San Luis Pass, Texas
* East of Morgan City Louisiana to the mouth of the Pearl River,
including New Orleans
* Lake Pontchartrain and Lake Maurepas

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 700 PM CDT (0000 UTC), the center of Hurricane Delta was located
near latitude 30.0 North, longitude 93.0 West.  Delta is moving
toward the north-northeast near 14 mph (22 km/h), and this motion is
expected to continue through Saturday morning.  A motion toward the
northeast is then expected through Sunday night.  On the forecast
track, the center of Delta should move across central and
northeastern Louisiana tonight and Saturday morning.  After that
time, the system is forecast to move across northern Mississippi
into the Tennessee Valley.

Maximum sustained winds are near 90 mph (150 km/h) with higher
gusts.  Rapid weakening is expected overnight and Saturday.  Delta
is forecast to weaken to a tropical storm tonight and to a tropical
depression on Saturday.

Hurricane-force winds extend outward up to 40 miles (65 km) from
the center and tropical-storm-force winds extend outward up to 160
miles (260 km).  The National Weather Service office at Lake Charles
reported sustained winds of 64 mph (103 km/h) with gusts to 95 mph
(153 km/h) at the airport.

The estimated minimum central pressure is 971 mb (28.67 inches).


HAZARDS AFFECTING LAND
----------------------
Key messages for Delta can be found in the Tropical Cyclone
Discussion under AWIPS header MIATCDAT1, WMO header WTNT41
KNHC, and on the web at www.hurricanes.gov/text/MIATCDAT1.shtml.

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...

Rockefeller Wildlife Refuge, LA to Morgan City, LA including
Vermilion Bay...7-11 ft
Holly Beach, LA to Rockefeller Wildlife Refuge, LA...5-8 ft
Morgan City, LA to Port Fourchon, LA...4-6 ft
Sabine Pass to Holly Beach, LA...2-4 ft
Calcasieu Lake...2-4 ft
Port Fourchon, LA to the Mouth of the Pearl River...2-4 ft
Lake Borgne...2-4 ft
Lake Pontchartrain and Lake Maurepas...1-3 ft
Mouth of the Pearl River to the AL/FL border including Mobile
Bay...1-3 ft
Sabine Lake...1-3 ft
Port O'Connor, TX to Sabine Pass including Galveston Bay...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.

WIND:  Hurricane conditions are occurring within the hurricane
warning area, and should continue during the next few hours.
Tropical storm conditions will continue within portions of the
tropical storm warning areas through early Saturday.

RAINFALL:  Today through Saturday, Delta is expected to produce 5 to
10 inches of rain, with isolated maximum totals of 15 inches, from
southwest into central Louisiana.  These rainfall amounts will lead
to significant flash, urban, small stream flooding, along with minor
to major river flooding.

For extreme east Texas into northern Louisiana, southern Arkansas,
and western Mississippi, Delta is expected to produce 3 to 6 inches
of rain, with isolated maximum totals of 10 inches.  These rainfall
amounts will lead to flash, urban, small stream, and isolated minor
river flooding.

As the remnants of Delta move farther inland, 1 to 3 inches of rain,
with locally higher amounts, are expected in the Tennessee Valley
and Mid Atlantic this weekend.  There is a potential for 3 to 6
inches in the Southern Appalachians, which could lead to isolated
flash, urban, and small stream flooding.

TORNADOES:  A few tornadoes are possible through tonight over the
southern portions of Louisiana and Mississippi.

SURF:  Swells from Delta are affecting portions of the northern and
western Gulf coast.  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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