Hurricane Delta Intermediate Advisory # 12A

BULLETIN
Hurricane Delta Intermediate Advisory Number 12A
NWS National Hurricane Center Miami FL       AL262020
100 PM CDT Wed Oct 07 2020

...AIR FORCE HURRICANE HUNTER AIRCRAFT INVESTIGATING DELTA OVER THE 
SOUTHERN GULF OF MEXICO...


SUMMARY OF 100 PM CDT...1800 UTC...INFORMATION
----------------------------------------------
LOCATION...21.8N 88.8W
ABOUT 115 MI...185 KM W OF CABO CATOCHE MEXICO
ABOUT 65 MI...110 KM ENE OF PROGRESO MEXICO
MAXIMUM SUSTAINED WINDS...100 MPH...155 KM/H
PRESENT MOVEMENT...NW OR 305 DEGREES AT 17 MPH...28 KM/H
MINIMUM CENTRAL PRESSURE...975 MB...28.80 INCHES


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

The government of Mexico has discontinued the Tropical Storm 
Warning along the east coast of the Yucatan peninsula from Punta 
Herrero to Tulum. 

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Watch is in effect for...
* High Island, Texas, to the Alabama/Florida border including
Calcasieu Lake, Vermilion Bay, Lake Pontchartrain, Lake Maurepas,
Lake Borgne and Mobile Bay

A Hurricane Warning is in effect for...
* Tulum to Dzilam Mexico
* Cozumel

A Hurricane Watch is in effect for...
* High Island Texas to Grand Isle Louisiana

A Tropical Storm Warning is in effect for...
* Dzilam to Progreso Mexico

A Tropical Storm Watch is in effect for...
* San Luis Pass to west of High Island Texas
* East of Grand Isle Louisiana to Bay St. Louis Mississippi,
including New Orleans
* Lake Pontchartrain and Lake Maurepas

A Hurricane Warning means that hurricane conditions are expected
somewhere within the warning area.

A Storm Surge Watch means there is a possibility of life-
threatening inundation, from rising water moving inland from the
coastline, in the indicated locations during the next 48 hours.
For a depiction of areas at risk, please see the National Weather
Service Storm Surge Watch/Warning Graphic, available at
hurricanes.gov.

A Hurricane Watch means that hurricane conditions are possible
within the watch area.  A watch is typically issued 48 hours
before the anticipated first occurrence of tropical-storm-force
winds, conditions that make outside preparations difficult or
dangerous.

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, generally within 48 hours.

For storm information specific to your area, please monitor
products issued by your national meteorological service.


DISCUSSION AND OUTLOOK
----------------------
At 100 PM CDT (1800 UTC), the center of Hurricane Delta was located
near latitude 21.8 North, longitude 88.8 West. Delta is moving
toward the northwest near 17 mph (28 km/h).  A northwestward motion
with a reduction in forward speed is expected over the next 24
hours.  A north-northwestward motion is expected by late Thursday,
and a faster northward to north-northeastward motion is forecast on
Friday and Friday night.  On the forecast track, the center of Delta
will move over the southern Gulf of Mexico this afternoon, be over
the southern or central Gulf of Mexico through Thursday, and
approach the northern Gulf coast within the hurricane watch area on
Friday.

Maximum sustained winds are near 100 mph (155 km/h) with higher
gusts.  Re-strengthening is forecast when the hurricane moves over
the southern and central Gulf of Mexico through Thursday, and Delta
is expected to become a major hurricane again.  Some weakening is is
forecast as Delta approaches the northern Gulf coast on Friday.

Hurricane-force winds extend outward up to 30 miles (45 km) from
the center and tropical-storm-force winds extend outward up to 125
miles (205 km).

The estimated minimum central pressure is 975 mb (28.80 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:  A life-threatening storm surge will raise water levels
in areas of onshore winds by as much as 6 to 9 ft above normal
tide levels along the northern coast of the Yucatan Peninsula from
Cabo Catoche to Progreso.  Near the coast, the surge will be 
accompanied by large and destructive waves.

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...

Pecan Island, LA to Port Fourchon, LA including Vermilion
Bay...7-11 ft
Cameron, LA to Pecan Island, LA...4-7 ft
Port Fourchon, LA to Ocean Springs, MS including Lake
Borgne...4-6 ft
Lake Pontchartrain and Lake Maurepas...3-5 ft
Ocean Springs, MS to AL/FL border including Mobile Bay...2-4 ft
High Island, TX to Cameron, LA including Calcasieu Lake...2-4 ft
Sabine Lake...1-3 ft
Port O'Connor, TX to High Island, TX 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 and tropical storm conditions will continue within
the warning area in the Yucatan peninsula during the next few
hours.  Tropical storm conditions are possible within the watch
areas along the Gulf coast by late Thursday night or early Friday
with hurricane conditions possible within the hurricane watch area
by Friday morning.

RAINFALL:  Through early Thursday, Delta is expected to produce 4 to
6 inches of rain, with isolated maximum totals of 10 inches, across
portions of the northern Yucatan Peninsula. This rainfall may result
in areas of significant flash flooding.

Friday through Saturday, Delta is expected to produce 4 to 8 inches
of rain, with isolated maximum totals of 12 inches across portions
of the central Gulf Coast north into portions of the Lower to Middle
Mississippi Valley. These rainfall amounts will lead to flash,
urban, small stream, and minor river flooding. As Delta moves
farther inland, 1 to 3 inches of rain, with locally higher amounts,
is expected in the Ohio Valley and Mid Atlantic this weekend.

SURF:  Swells generated by Delta will affect land areas around the
northwestern Caribbean Sea today. Swells will begin to affect
portions of the northern and western Gulf coast on Thursday. 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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