Irma: Cat 4
September 5th, 2017000
WTNT31 KNHC 050846
TCPAT1
BULLETIN
Hurricane Irma Advisory Number 24
NWS National Hurricane Center Miami FL AL112017
500 AM AST Tue Sep 05 2017
…DANGEROUS HURRICANE IRMA HEADING FOR THE LEEWARD ISLANDS WITH 150
MPH WINDS…
SUMMARY OF 500 AM AST…0900 UTC…INFORMATION
———————————————-
LOCATION…16.6N 57.0W
ABOUT 320 MI…515 KM E OF THE LEEWARD ISLANDS
MAXIMUM SUSTAINED WINDS…150 MPH…240 KM/H
PRESENT MOVEMENT…W OR 270 DEGREES AT 14 MPH…22 KM/H
MINIMUM CENTRAL PRESSURE…937 MB…27.67 INCHES
WATCHES AND WARNINGS
——————–
CHANGES WITH THIS ADVISORY:
The government of Barbados has issued a Tropical Storm Warning for
Dominica.
SUMMARY OF WATCHES AND WARNINGS IN EFFECT:
A Hurricane Warning is in effect for…
* Antigua, Barbuda, Anguilla, Montserrat, St. Kitts, and Nevis
* Saba, St. Eustatius, and Sint Maarten
* Saint Martin and Saint Barthelemy
* British Virgin Islands
* U.S. Virgin Islands
* Puerto Rico, Vieques, and Culebra
A Hurricane Watch is in effect for…
* Guadeloupe
A Tropical Storm Warning is in effect for…
* Guadeloupe
* Dominica
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. In this case, for some of easternmost islands, the
hurricane conditions are expected within the next 24 hours.
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 in this case within 36
hours.
Interests in the Dominican Republic, Haiti, the Turks and Caicos
Islands, Cuba, and the southeastern and central Bahamas should
monitor the progress of Irma.
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
the United States, please monitor products issued by your national
meteorological service.
DISCUSSION AND 48-HOUR OUTLOOK
——————————
At 500 AM AST (0900 UTC), the distinct eye of Hurricane Irma was
located near latitude 16.6 North, longitude 57.0 West. Irma is
moving toward the west near 14 mph (22 km/h), and this general
motion is expected to continue today, followed by a turn toward the
west-northwest tonight. On the forecast track, the core of Irma
will move near or over portions of the northern Leeward Islands
tonight and early Wednesday.
Maximum sustained winds have increased to near 150 mph (240 km/h)
with higher gusts. Irma is a category 4 hurricane on the
Saffir-Simpson Hurricane Wind Scale. A NOAA Hurricane Hunter
plane is scheduled to be in the eye of Irma within the hour.
Some fluctuations in intensity are likely during the next day
or two, but Irma is forecast to remain a powerful category 4
hurricane.
Hurricane-force winds extend outward up to 45 miles (75 km) from the
center and tropical-storm-force winds extend outward up to 140 miles
(220 km).
The estimated minimum central pressure is 937 mb (27.67 inches).
HAZARDS AFFECTING LAND
———————-
STORM SURGE: The combination of a dangerous storm surge and large
breaking waves will raise water levels by as much as 6 to 9 feet
above normal tide levels along the coasts of the extreme northern
Leeward Islands within the hurricane warning area near and to the
north of the center of Irma. 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 is expected to reach
the following heights above ground if the peak surge occurs at the
time of high tide…
British and U.S. Virgin Islands except St. Croix…4 to 6 ft
Northern coast of Puerto Rico…2 to 4 ft
Southern coast of Puerto Rico and St. Croix…1 to 2 ft
The deepest water will occur along the immediate coast in areas of
onshore winds, where the surge will be accompanied by large and
destructive 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 tonight, with tropical storm conditions
beginning later today. Tropical storm conditions are expected within
the tropical storm warning area where hurricane conditions are also
possible.
RAINFALL: Irma is expected to produce total rainfall accumulations
of 4 to 8 inches with isolated maximum amounts of 12 inches across
the northern Leeward Islands, the British and U.S. Virgin Islands,
and Puerto Rico. These rainfall amounts may cause life-threatening
flash floods and mudslides.
SURF: Swells generated by Irma will affect the northern Leeward
Islands, Puerto Rico, and the U.S. and British Virgin Islands
during the next several days. These swells are likely to cause
life-threatening surf and rip current conditions. Please consult
products from your local weather office.
NEXT ADVISORY
————-
Next intermediate advisory at 800 AM AST.
Next complete advisory at 1100 AM AST.
$$
Forecaster Avila