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Tropical Storm ISAIAS


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BULLETIN
Tropical Storm Isaias Advisory Number  10
NWS National Hurricane Center Miami FL       AL092020
500 PM EDT Thu Jul 30 2020
 
...ISAIAS CONTINUES TO BRING HEAVY RAINFALL AND TROPICAL-STORM-FORCE
WINDS TO PORTIONS OF THE DOMINICAN REPUBLIC...
...FORECAST TO BECOME A HURRICANE FRIDAY OR FRIDAY NIGHT...
 
 
SUMMARY OF 500 PM EDT...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...19.5N 70.6W
ABOUT 155 MI...250 KM WNW OF PUNTA CANA DOMINICAN REPUBLIC
ABOUT 250 MI...400 KM SE OF THE SOUTHEASTERN BAHAMAS
MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/H
PRESENT MOVEMENT...NW OR 310 DEGREES AT 20 MPH...31 KM/H
MINIMUM CENTRAL PRESSURE...999 MB...29.50 INCHES
 
 
WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:
 
The government of the Bahamas has issued a Tropical Storm Warning
for the northwest Bahamas.
 
A Tropical Storm Watch has been issued for the east coast of
Florida from Ocean Reef northward to Sebastian Inlet.
 
SUMMARY OF WATCHES AND WARNINGS IN EFFECT:
 
A Tropical Storm Warning is in effect for...
* Dominican Republic entire southern and northern coastlines
* North coast of Haiti from Le Mole St Nicholas eastward to the
northern border with the Dominican Republic
* Turks and Caicos Islands
* Southeastern Bahamas including the Acklins, Crooked Island, Long
Cay, the Inaguas, Mayaguana, and the Ragged Islands
* Central Bahamas, including Cat Island, the Exumas, Long Island,
Rum Cay, and San Salvador
* Northwestern Bahamas including Andros Island, New Providence,
Eleuthera, Abacos Islands, Berry Islands, Grand Bahamas Island, and
Bimini
 
A Tropical Storm Watch is in effect for...
* East coast of Florida from Ocean Reef to Sebastian Inlet
 
The Tropical Storm Warnings for the central and northwest Bahamas
may be upgraded to Hurricane Warnings this evening or tonight.
 
Interests elsewhere along the southeast coast of the United
States should monitor the progress of this system.  Additional
watches or warnings may be required for a portion of the Florida
peninsula tonight or Friday.
 
A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area within 36 hours.
 
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 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 500 PM EDT (2100 UTC), the center of Tropical Storm Isaias was
located near latitude 19.5 North, longitude 70.6 West. Isaias is 
moving toward the northwest near 20 mph (31 km/h) and a 
northwestward motion with some decrease in forward speed is expected 
over the next couple of days.  On the forecast track, the center of 
Isaias will move near the Southeastern Bahamas by late tonight. 
Isaias is forecast to be near the Central Bahamas Friday night and 
move near or over the Northwest Bahamas and near South Florida on 
Saturday.
 
Maximum sustained winds are near 60 mph (95 km/h) with higher gusts.
Strengthening is forecast during the next day or so, and Isaias is 
forecast to become a hurricane on Friday or Friday night. 
 
Tropical-storm-force winds extend outward up to 240 miles (390 km)
from the center.
 
The estimated minimum central pressure based on surface 
observations in the Dominican Republic is 999 mb (29.50 inches).
 
 
HAZARDS AFFECTING LAND
----------------------
Key messages for Isaias can be found in the Tropical Cyclone
Discussion under AWIPS header MIATCDAT4, WMO header WTNT44 KNHC, and
on the web at www.hurricanes.gov/text/MIATCDAT4.shtml.

STORM SURGE:  A dangerous storm surge will raise water levels by as 
much as 3 to 5 feet above normal tide levels in areas of onshore 
flow in the central and northwest Bahamas. Storm surge will raise 
water level by as much as 1 to 3 ft above normal tide levels in the 
southeastern Bahamas.

WIND:  Tropical storm conditions will continue to spread across
portions of the Dominican Republic, Haiti, the southeastern Bahamas 
and Turks and Caicos within the warning area tonight. Tropical storm 
conditions are expected to begin in the central Bahamas Friday 
morning and spread into the northwestern Bahamas beginning late 
Friday.  Hurricane conditions are expected within portions of the 
the central and northwestern Bahamas Friday night and Saturday.  

Tropical storm conditions are possible in the watch area in Florida 
beginning Saturday. 
 
RAINFALL: Isaias is expected to produce the following rain 
accumulations:

Puerto Rico, Dominican Republic and northern Haiti: 4 to 8 inches, 
with isolated maximum totals of 12 inches.

Bahamas, Turks and Caicos: 4 to 8 inches.

Cuba: 1 to 2 inches, with isolated maximum totals of 4 inches.

These rainfall amounts will lead to life-threatening flash flooding 
and mudslides, as well as river flooding.  Urban and small stream 
flooding is expected for the U.S. Virgin Islands, eastern and 
southwestern Puerto Rico, and Hispaniola.

Heavy rains associated with Isaias may begin to affect eastern 
Florida over the weekend. This rain could result in isolated flash 
and urban flooding, especially in low-lying and poorly drained 
areas. 
 
SURF:  Swells generated by Isaias are affecting portions of
the Leeward Islands, the Virgin Islands, Puerto Rico, the Dominican
Republic, the Turks and Caicos Islands and the southeastern
Bahamas. These swells will spread along the coast of Cuba and into 
the central and northwestern Bahamas over the next day or two. 
These swells are likely to cause life-threatening surf and rip 
current conditions.  Please consult products from your local 
weather office.
 
 
NEXT ADVISORY
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Next intermediate advisory at 800 PM EDT.
Next complete advisory at 1100 PM EDT.
 
$$
Forecaster Brown
 
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