000 WTNT31 KNHC 110002 CCA TCPAT1 BULLETIN Potential Tropical Cyclone Six Intermediate Advisory Number 5A... Corrected NWS National Hurricane Center Miami FL AL062021 800 PM AST Tue Aug 10 2021 Corrected direction of motion in summary section. ...DISTURBANCE LOCATED JUST SOUTH OF PUERTO RICO... ...SYSTEM LIKELY TO BECOME A TROPICAL STORM TONIGHT... SUMMARY OF 800 PM AST...0000 UTC...INFORMATION ---------------------------------------------- LOCATION...17.6N 66.1W ABOUT 40 MI...60 KM SE OF PONCE PUERTO RICO ABOUT 240 MI...390 KM ESE OF SANTO DOMINGO DOMINICAN REPUBLIC MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H PRESENT MOVEMENT...W OR 270 DEGREES AT 17 MPH...28 KM/H MINIMUM CENTRAL PRESSURE...1009 MB...29.80 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: None. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Tropical Storm Warning is in effect for... * Puerto Rico, including Culebra and Vieques * U.S. Virgin Islands * Dominican Republic on the south coast from Punta Palenque eastward and on the north coast from Cabo Frances Viejo eastward A Tropical Storm Watch is in effect for... * Dominican Republic on the north coast from Cabo Frances Viejo to the Dominican Republic/Haiti border * Haiti from the northern border with the Dominican Republic to Gonaives * Turks and Caicos Islands * Southeastern Bahamas 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. Interests elsewhere in Haiti and the Bahamas, as well as in eastern and central Cuba, should monitor the progress of this system. 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 PM AST (0000 UTC), the disturbance was located by an Air Force Reserve reconnaissance aircraft and Doppler radar data from San Juan near latitude 17.6 North, longitude 66.1 West. The system is moving toward the west near 17 mph (28 km/h) and this general motion is expected to continue tonight. A turn back toward the west-northwest is forecast to occur early Wednesday, with a west-northwestward motion continuing during the next few days. On the forecast track, the disturbance is expected to pass near the southern coast of Puerto Rico tonight and early Wednesday, be near or over Hispaniola on Wednesday, and be near the southeastern Bahamas and the Turks and Caicos Islands on Thursday. Data from the aircraft and surface observations indicate that maximum sustained winds have increased to near 40 mph (65 km/h) with higher gusts. Gradual strengthening is forecast during the next day or so and the disturbance is expected to become a tropical storm later tonight. Some weakening is likely while the system interacts with Hispaniola on Wednesday. * Formation chance through 48 hours...high...90 percent. * Formation chance through 5 days...high...90 percent. The estimated minimum central pressure based on data from the aircraft and earlier surface observations is 1009 mb (29.80 inches). Tropical-storm-force winds extend outward up to 40 miles (65 km), mainly northeast of the center. During the past few hours, a sustained wind of 38 mph (61 km/h) and a gust to 49 mph (79 km/h) were measured by a Weatherflow observing station at Sandy Point on the western end of St. Croix. A wind gust to 47 mph (76 km/h) was reported near Yabucoa in southeastern Puerto Rico. HAZARDS AFFECTING LAND ---------------------- Key messages for Potential Tropical Cyclone Six can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDAT1, WMO header WTNT41 KNHC and on the web at www.hurricanes.gov/graphics_at1.shtml?key_messages. RAINFALL: The system is expected to produce the following rainfall amounts: Over the Leeward Islands, Virgin Islands, Puerto Rico, and the Dominican Republic...2 to 4 inches, with isolated maximum totals of 6 inches. Heavy rainfall could lead to flash, urban, and small stream flooding, along with possible rapid river rises and the potential for mudslides across the U.S. Virgin Islands, Puerto Rico, and the Dominican Republic. Over Haiti, the Turks and Caicos, eastern Bahamas, and eastern Cuba...1 to 3 inches with isolated maximum totals of 5 inches. WIND: Tropical storm conditions are expected in the warning areas in the U.S. Virgin Islands and Puerto Rico during the next several hours, and in the warning area in the Dominican Republic by early Wednesday. Tropical storm conditions are possible elsewhere along the northern coasts of the Dominican Republic, northern Haiti, the Turks and Caicos, and the southeastern Bahamas beginning late Wednesday. SURF: Swells generated by the disturbance are affecting portions of the Leeward Islands. These swells are expected to spread across the U.S. Virgin Islands and Puerto Rico today and reach portions of Hispaniola on Wednesday, where they could cause life-threatening surf and rip current conditions. Please consult products from your local weather office. NEXT ADVISORY ------------- Next complete advisory at 1100 PM AST. $$ Forecaster Stewart