Delta Advisory # 17A

BULLETIN
Hurricane Delta Intermediate Advisory Number 17A
NWS National Hurricane Center Miami FL       AL262020
700 PM CDT Thu Oct 08 2020

...DELTA EXPECTED TO BRING HURRICANE CONDITIONS AND A
LIFE-THREATENING STORM SURGE TO PORTIONS OF THE NORTHERN GULF COAST
ON FRIDAY...


SUMMARY OF 700 PM CDT...0000 UTC...INFORMATION
----------------------------------------------
LOCATION...25.3N 93.5W
ABOUT 310 MI...500 KM S OF CAMERON LOUISIANA
MAXIMUM SUSTAINED WINDS...115 MPH...185 KM/H
PRESENT MOVEMENT...NNW OR 330 DEGREES AT 12 MPH...19 KM/H
MINIMUM CENTRAL PRESSURE...956 MB...28.23 INCHES


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

None.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Warning is in effect for...
* High Island Texas to Ocean Springs Mississippi including
Calcasieu Lake, Vermilion Bay, Lake Pontchartrain, Lake Maurepas,
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 Sargent Texas
* East of Morgan City Louisiana to the mouth of the Pearl River,
including New Orleans
* Lake Pontchartrain and Lake Maurepas

A Tropical Storm Watch is in effect for...
* East of the mouth of the Pearl River to Bay St. Louis Mississippi

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.  A warning is typically issued 36
hours before the anticipated first occurrence of tropical-storm-
force winds, conditions that make outside preparations difficult or
dangerous.  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.

A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area.

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 25.3 North, longitude 93.5 West.  Delta is moving
toward the north-northwest near 12 mph (19 km/h).  A turn toward the
north is forecast overnight, followed by a north-northeastward
motion Friday and Friday night.  On the forecast track, the center
of Delta will move over the northwestern Gulf of Mexico on Friday,
and then move inland within the hurricane warning area Friday
afternoon or Friday night.

Maximum sustained winds are near 115 mph (185 km/h) with higher
gusts.  Delta is a category 3 hurricane on the Saffir-Simpson
Hurricane Wind Scale.  Additional strengthening is possible tonight.
Some weakening is anticipated as Delta approaches the northern Gulf
coast on Friday, with rapid weakening expected after the center
moves inland.

Hurricane-force winds extend outward up to 35 miles (55 km) from
the center and tropical-storm-force winds extend outward up to 160
miles (260 km).  NOAA buoy 42002, just to the north of Delta's 
center, recently measured a sustained wind of 54 mph (86 km/h) and 
a wind gust to 65 mph (104 km/h).

The minimum central pressure estimated from Hurricane Hunter
observations is 956 mb (28.23 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
Sabine Pass to Holly Beach, LA...4-7 ft
Morgan City, LA to Port Fourchon, LA...4-7 ft
Port Fourchon, LA to the Mouth of the Mississippi River...3-5 ft
Calcasieu Lake...3-5 ft
High Island, TX to Sabine Pass...2-4 ft
Mouth of the Mississippi River to Ocean Springs, MS...2-4 ft
Lake Borgne, Lake Pontchartrain, and Lake Maurepas...2-4 ft
Ocean Springs, MS to the AL/FL border including Mobile Bay...1-3 ft
Sabine Lake...1-3 ft
Port O'Connor, TX to High Island, TX including Galveston Bay...
1-3 ft

It is important to note that small changes in the track, structure,
or intensity of Delta could have large impacts on where the highest
storm surge occurs.  Users are urged to stay tuned for possible
changes and updates.

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 expected within the hurricane
warning area by Friday afternoon or evening, with tropical storm
conditions expected within this area by early Friday.  Tropical
storm conditions are expected within the tropical storm warning
areas on Friday, and are possible within the tropical storm watch
area Friday night.

RAINFALL:  Friday through Saturday, Delta is expected to produce 5
to 10 inches of rain, with isolated maximum totals of 15 inches,
from southwest into south-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 Delta moves farther inland, 1 to 3 inches of rain, with locally
higher amounts, are expected in the Tennessee Valley and Mid-
Atlantic this weekend.

TORNADOES:  There is a risk of a few tornadoes beginning late
tonight and continuing through Friday over southern portions of
Louisiana and Mississippi.

SURF:  Swells from Delta will begin to affect portions of the
northern and western Gulf coast during the next several hours.
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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