BULLETIN Hurricane Ida Intermediate Advisory Number 5A
NWS National Hurricane Center Miami FL AL092021
200 PM EDT Fri Aug 27 2021
…IDA MAKES LANDFALL AS A HURRICANE ON THE ISLE OF YOUTH…
SUMMARY OF 200 PM EDT…1800 UTC…INFORMATION
———————————————-
LOCATION…21.6N 82.7W
ABOUT 5 MI…10 KM E OF THE CENTER OF THE ISLE OF YOUTH
ABOUT 145 MI…245 KM E OF THE WESTERN TIP OF CUBA
MAXIMUM SUSTAINED WINDS…75 MPH…120 KM/H
PRESENT MOVEMENT…NW OR 325 DEGREES AT 15 MPH…24 KM/H
MINIMUM CENTRAL PRESSURE…987 MB…29.15 INCHES
WATCHES AND WARNINGS
——————–
CHANGES WITH THIS ADVISORY:
The government of the Cayman Islands has discontinued all Tropical
Storm Warnings.
SUMMARY OF WATCHES AND WARNINGS IN EFFECT:
A Hurricane Warning is in effect for…
* Cuban provinces of Pinar del Rio and Artemisa, and the Isle of
Youth
A Storm Surge Watch is in effect for…
* Sabine Pass to Alabama/Florida border
* Vermilion Bay, Lake Borgne, Lake Pontchartrain, Lake Maurepas, and
Mobile Bay
A Hurricane Watch is in effect for…
* Cameron, Louisiana to the Mississippi/Alabama border
* Lake Pontchartrain, Lake Maurepas, and Metropolitan New Orleans
A Tropical Storm Warning is in effect for…
* Cuban provinces of Matanzas, Mayabeque, and Havana
A Tropical Storm Watch is in effect for…
* Mississippi/Alabama border to the Alabama/Florida border.
A Hurricane Warning means that hurricane conditions are expected
somewhere within the warning area.
A Tropical Storm Warning means that tropical storm 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 Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.
Interests elsewhere in central and western Cuba and elsewhere along
the northern U.S. Gulf coast should monitor the progress of this
system. Hurricane warnings will likely be required for portions of
the northern Gulf coast later today. Interests in the Dry Tortugas
should also monitor the progress of Ida.
For storm information specific to your area in the United
States, including possible inland watches and warnings, please
monitor products issued by your local National Weather Service
forecast office. For storm information specific to your area
outside of the United States, please monitor products issued by
your national meteorological service.
DISCUSSION AND OUTLOOK
———————-
At 200 PM EDT (1800 UTC), the center of Hurricane Ida was located
by Cuban radar and Air Force Reserve Hurricane Hunter aircraft near
latitude 21.6 North, longitude 82.7 West. Ida is moving toward the
northwest near 15 mph (24 km/h), and this general motion should
continue over the next few days. On the forecast track, the
center of Ida will pass over the Isle of Youth during the next
hour or so, move over western Cuba later today, and move over the
southeastern and central Gulf of Mexico tonight and Saturday. Ida
is forecast to make landfall along the U.S. northern Gulf coast
within the hurricane watch area on Sunday.
Reports from Air Force Reserve reconnaissance aircraft indicate
that the maximum sustained winds are near 75 mph (120 km/h) with
higher gusts. Additional strengthening is forecast before the
center moves over western Cuba later today. Steady to rapid
strengthening is expected when Ida moves over the southeastern and
central Gulf of Mexico over the weekend, and Ida is expected to be
a major hurricane when it approaches the northern Gulf coast.
Hurricane-force winds extend outward up to 20 miles (30 km) from the
center. Tropical-storm-force winds extend outward up to 90 miles
(150 km) from the center. Sustained winds of 38 mph (61 km/h) and a
gust to 55 mph (89 km/h) has recently been observed on Cayo Largo,
Cuba.
The latest minimum central pressure estimated from Air Force
Reserve reconnaissance aircraft data is 987 mb (29.15 inches).
HAZARDS AFFECTING LAND
———————-
Key messages for Ida can be found in the Tropical Cyclone
Discussion under AWIPS header MIATCDAT4, WMO header WTNT44 KNHC,
and on the web at hurricanes.gov/graphics_at4.shtml?key_messages.
STORM SURGE: A dangerous storm surge will raise water levels by
as much as 4 to 6 feet above normal tide levels in areas of onshore
winds along the immediate coast of the Isle of Youth and near and to
the east of where the center crosses the coast of western Cuba.
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…
Morgan City, LA to Ocean Springs, MS including Lake Borgne…7-11 ft
Rockefeller Wildlife Refuge, LA to Morgan City, LA including
Vermilion Bay…4-7 ft
Ocean Springs, MS to MS/AL border…4-7 ft
MS/AL border to AL/FL border including Mobile Bay…3-5 ft
Lake Pontchartrain…4-6 ft
Lake Maurepas…3-5 ft
Sabine Pass to Rockefeller Wildlife Refuge, LA…2-4 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. For information
specific to your area, please see products issued by your local
National Weather Service forecast office.
WIND: Hurricane conditions are occuring over the Isle of Youth
and are expected to spread over portions of western Cuba in the
hurricane warning area by later this afternoon and evening.
Tropical storm conditions are already beginning to reach portions
of western Cuba and will continue through early Saturday.
Hurricane conditions are possible in the hurricane watch area along
the northern Gulf coast late Saturday night or Sunday and tropical
storm conditions are possible in the watch area late Saturday night
or Sunday.
RAINFALL: Ida is expected to produce total rainfall accumulations
of 6 to 10 inches with maximum totals of 15 inches across Jamaica.
Rainfall totals of 8 to 12 inches with isolated maximum amounts of
20 inches are expected across the Cayman Islands and western Cuba,
including the Isle of Youth. These rainfall amounts may produce
life-threatening flash floods and mudslides.
As Ida approaches the central Gulf Coast Sunday afternoon, total
rainfall accumulations of 8 to 16 inches with isolated maximum
amounts of 20 inches are possible from southeast Louisiana to
coastal Mississippi and Alabama through Monday morning. Ida is
forecast to turn northeast as it moves inland later Monday with
rainfall totals of 4 to 8 inches possible across southern and
central Mississippi. This is likely to result in considerable flash,
urban, small stream, and riverine flooding.
SURF: Swells generated by this system will affect the Cayman
Islands and Cuba through tonight. Swells will begin reaching
portions of the northern Gulf coast Saturday night or early Sunday.
These swells are likely to cause life-threatening surf and rip
current conditions. Please consult products from your local weather
office.
