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ZCZC MIATCPAT1 ALL TTAA00 KNHC DDHHMM BULLETIN Hurricane Irma Advisory Number 29 NWS National Hurricane Center Miami FL AL112017 500 AM AST Wed Sep 06 2017 ...EYE OF POTENTIALLY CATASTROPHIC CATEGORY 5 HURRICANE IRMA MOVING AWAY FROM BARBUDA AND TOWARD ST. MARTIN... SUMMARY OF 500 AM AST...0900 UTC...INFORMATION ---------------------------------------------- LOCATION...17.9N 62.6W ABOUT 35 MI...55 KM ESE OF ST. MARTIN ABOUT 145 MI...235 KM E OF ST. CROIX MAXIMUM SUSTAINED WINDS...185 MPH...295 KM/H PRESENT MOVEMENT...WNW OR 285 DEGREES AT 16 MPH...26 KM/H MINIMUM CENTRAL PRESSURE...914 MB...26.99 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: The Government of the Bahamas has issued a Hurricane Warning for the Southeastern Bahamas and the Turks and Caicos Islands, and a Hurricane Watch for the Central Bahamas. The Meteorological Service of Barbados has discontinued the 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 * Dominican Republic from Cabo Engano to the northern border with Haiti * Guadeloupe * Southeastern Bahamas and the Turks and Caicos Islands A Hurricane Watch is in effect for... * Haiti from the northern border with the Dominican Republic to Le Mole St. Nicholas * Turks and Caicos Islands * Southeastern Bahamas * Cuba from Matanzas province eastward to Guantanamo province * Central Bahamas A Tropical Storm Warning is in effect for... * Dominican Republic from south of Cabo Engano westward to the southern border with Haiti A Tropical Storm Watch is in effect for... * Haiti from south of Le Mole St. Nicholas to Port-Au-Prince 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 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 Warning means that tropical storm conditions are expected somewhere within the warning area. A Tropical Storm Watch means that tropical storm conditions are possible within the watch area, generally within 48 hours. Interests elsewhere in the Dominican Republic and Haiti, as well as Cuba, the northwestern Bahamas, and Florida 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 center of Hurricane Irma was located near latitude 17.9 North, longitude 62.6 West. Irma is moving toward the west-northwest near 16 mph (26 km/h), and this general motion is expected to continue for the next couple of days. On the forecast track, the extremely dangerous core of Irma will move over portions of the northern Leeward Islands this morning, move near or over portions of the northern Virgin Islands later today, and pass near or just north of Puerto Rico this afternoon or tonight. Maximum sustained winds remain near 185 mph (295 km/h) with higher gusts. Irma is a category 5 hurricane on the Saffir-Simpson Hurricane Wind Scale. Some fluctuations in intensity are likely during the next day or two, but Irma is forecast to remain a powerful category 4 or 5 hurricane during the next couple of days. Hurricane-force winds extend outward up to 50 miles (85 km) from the center and tropical-storm-force winds extend outward up to 175 miles (280 km). St. Martin recently reported a wind gust of 61 mph (98 km/h). The estimated minimum central pressure is 914 mb (26.99 inches). HAZARDS AFFECTING LAND ---------------------- STORM SURGE: The combination of a life-threatening storm surge and large breaking waves will raise water levels ABOVE NORMAL TIDE LEVELS by the following amounts 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. Northern Leeward Islands...7 to 11 ft Turks and Caicos Islands...15 to 20 ft Southeastern Bahamas...15 to 20 ft Northern coast of the Dominican Republic...3 to 5 ft Northern coast of Haiti and the Gulf of Gonave...1 to 3 ft The combination of a life-threatening 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...7 to 11 ft Northern coast of Puerto Rico...3 to 5 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 occuring within the hurricane warning area in the Leeward Islands and should continue through today. Hurricane conditions are expected to begin within the hurricane warning area in the British and U.S. Virgin Islands and Puerto Rico later today and tonight, with tropical storm conditions beginning this morning. Hurricane conditions are expected to begin within the hurricane warning area in the Dominican Republic early Thursday, with tropical storm conditions beginning tonight. Hurricane conditions are expected in the warning area in the southeastern Bahamas and the Turks and Caicos Islands beginning Thursday night. Hurricane and tropical storm conditions are possible within the watch area in Haiti by early Thursday and in the central Bahamas by Friday. RAINFALL: Irma is expected to produce the following rain accumulations through Thursday: Northern Leeward Islands...8 to 12 inches, isolated 20 inches Northeast Puerto Rico and the British and U.S. Virgin Islands...4 to 10 inches, isolated 15 inches Southwest Puerto Rico, the southern Leeward Islands, and Saint Croix...2 to 4 inches Irma is expected to produce the following rain accumulations Wednesday through Saturday: Southeast Bahamas, the Turks and Caicos and eastern to central Cuba...8 to 12 inches, isolated 20 inches Northern Dominican Republic and northern Haiti...4 to 10 inches, isolated 15 inches Southwest Haiti...1 to 4 inches In all areas this rainfall may cause life-threatening flash floods and mudslides. SURF: Swells generated by Irma will affect the northern Leeward Islands, Puerto Rico, the Virgin Islands, the southeastern Bahamas, the Turks and Caicos Islands, the northern coast of the Dominican Republic, and portions of the southeast coast of the United States 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 Beven NNNN