SAN JUAN – The National Hurricane Center issued the following advisory on Friday:
Hurricane Isaias Intermediate Advisory Number 13A
NWS National Hurricane Center Miami FL AL092020
800 AM EDT Fri Jul 31 2020
… STRONG WINDS AND HEAVY SQUALLS LASHING THE SOUTHEASTERN BAHAMAS AND THE TURKS AND CAICOS ISLANDS…
… HURRICANE CONDITIONS EXPECTED TODAY OVER PORTIONS OF THE BAHAMAS…
SUMMARY OF 800 AM EDT… 1200 UTC… INFORMATION
LOCATION… 21.3N 73.9W ABOUT 30 MI… 50 KM NW OF GREAT INAGUA ISLAND ABOUT 340 MI… 545 KM SE OF NASSAU MAXIMUM SUSTAINED WINDS… 80 MPH… 130 KM / H PRESENT MOVEMENT… NW OR 305 DEGREES AT 17 MPH… 28 KM / H MINIMUM CENTRAL PRESSURE… 990 MB… 29.24 INCHES
WATCHES AND WARNINGS
CHANGES WITH THIS ADVISORY:
The Tropical Storm Warning for Haiti has been discontinued.
SUMMARY OF WATCHES AND WARNINGS IN EFFECT:
A Hurricane Warning is in effect fo r… * Northwestern Bahamas including Andros Island, New Providence, Eleuthera, Abacos Islands, Berry Islands, Grand Bahamas Island, and Bimini * 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
A Tropical Storm Warning is in effect for… * Dominican Republic entire southern and northern coastlines * Turks and Caicos Islands
A Tropical Storm Watch is in effect for… * East coast of Florida from Ocean Reef to Sebastian Inlet * Lake Okeechobee
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 later today. The Tropical Storm Warning for the Dominican Republic will likely be discontinued later this morning.
A Hurricane Warning means that hurricane conditions are expected somewhere within the warning area. 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 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 800 AM EDT (1200 UTC ), the center of Hurricane Isaias was located by NOAA and Air Force Reserve Hurricane Hunter aircraft near latitude 21.3 North, longitude 73.9 West. Isaias is moving toward the northwest near 17 mph (28 km / h), and a generally northwestward motion with some decrease in forward speed is expected for the next couple of days followed by a turn toward the north-northwest. On the forecast track, the center of Isaias will move near or over the Southeastern Bahamas today. Isaias is forecast to be near the Central Bahamas tonight, and move near or over the Northwestern Bahamas and be near or east of the Florida peninsula on Saturday and Sunday.
Maximum sustained winds are near 80 mph (130 km / h) with higher gusts. Some strengthening is possible today, and Isaias is expected to remain a hurricane for the next few days.
Hurricane-force winds extend outward up to 45 miles (75 km) from the center and tropical-storm-force winds extend outward up to 205 miles (335 km). A private weather observing site at Long Bay Beach in Providenciales recently reported a sustained wind of 55 mph (86 km / h) and a gust to 59 mph (95 km / h).
Reports from the reconnaissance aircraft indicate that the minimum central pressure is 990 mb (29.24 inches).
HAZARDS AFFECTING LAND
1. Isaias will produce heavy rains and potentially life-threatening flash flooding and mudslides across the Dominican Republic, northern Haiti, Turks and Caicos, and the Bahamas. Heavy rains associated with Isaias may begin to affect South and east-Central Florida beginning late Friday night, and the eastern Carolinas by early next week, potentially resulting in isolated flash and urban flooding, especially in low-lying and poorly drained areas. Isolated minor river flooding is possible in the Carolinas early next week.
2. Hurricane conditions and dangerous storm surge are expected in portions of the Bahamas today and Saturday, and Hurricane Warnings are in effect for these areas. Preparations to protect life and property should be rushed to completion.
3. Tropical storm conditions are possible along portions of the Florida east coast beginning Saturday, and a Tropical Storm Watch remains in effect. While storm surge watches are not currently needed for this area, they may be required later today if the forecast track shifts closer to the coast. Heavy rains associated with Isaias may begin to affect South Florida and east-Central Florida beginning late tonight, potentially resulting in isolated flash and urban flooding, especially in low-lying and poorly drained areas.
4. There is a risk of impacts from winds, heavy rainfall, and storm surge late this weekend from the northeastern Florida coast and spreading northward along the remainder of the U.S. east coast through early next week. The details of the track and intensity forecast remain uncertain, and it is too soon to determine the magnitude and location of these potential impacts, but interests along the entire U.S. east coast should monitor the progress of Isaias and updates to the forecast.
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 winds in the Bahamas.  WIND: Tropical storm conditions will continue across portions of the Dominican Republic and the Turks and Caicos this morning. Hurricane conditions are expected to begin in the southeastern Bahamas this morning and spread into the central and northwestern Bahamas tonight and into Saturday.
Tropical storm conditions are possible in the watch area in Florida beginning Saturday.
RAINFALL: Isaias is expected to produce the following rain accumulations through Saturday:
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 and Hispaniola.
From Friday night through Monday:
South Florida into east-Central Florida: 2 to 4 inches, with isolated maximum totals of 6 inches.
These rainfall amounts could result in isolated flash and urban flooding, especially in low-lying and poorly drained areas.
Heavy rains associated with Isaias may begin to affect the eastern Carolinas by early next week. This rain could result in isolated flash and urban flooding, especially in low-lying and poorly drained areas, as well as isolated minor river flooding.
SURF: Swells generated by Isaias are affecting portions of 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 later today and along the east coast of Florida on Saturday. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office.