000 WTNT31 KNHC 032050 TCPAT1 BULLETIN Hurricane Irma Advisory Number 18 NWS National Hurricane Center Miami FL AL112017 500 PM AST Sun Sep 03 2017 ...HURRICANE WATCHES ISSUED FOR PORTIONS OF THE LEEWARD ISLANDS... ...NOAA HURRICANE HUNTER AIRCRAFT EN ROUTE TO IRMA... SUMMARY OF 500 PM AST...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...17.6N 49.8W ABOUT 790 MI...1275 KM E OF THE LEEWARD ISLANDS MAXIMUM SUSTAINED WINDS...115 MPH...185 KM/H PRESENT MOVEMENT...W OR 260 DEGREES AT 14 MPH...22 KM/H MINIMUM CENTRAL PRESSURE...969 MB...28.62 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: The government of Antigua has issued a Hurricane Watch for the islands of Antigua, Barbuda, Anguilla, Montserrat, St. Kitts, and Nevis. The government of the Netherlands has issued a Hurricane Watch for the islands of Saba, St. Eustatius, and Sint Maarten. The government of France has issued a Hurricane Watch for St. Martin and Saint Barthelemy. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Hurricane Watch is in effect for... * Antigua, Barbuda, Anguilla, Montserrat, St. Kitts, and Nevis * Saba, St. Eustatius, and Sint Maarten * Saint Martin and Saint Barthelemy Interests in the remainder of the Leeward Islands, the British and U.S. Virgin Islands, and Puerto Rico should monitor the progress of Irma. Additional Hurricane and Tropical Storm Watches may be required for portions of this area on Monday. For storm information specific to your area, please monitor products issued by your national meteorological service. DISCUSSION AND 48-HOUR OUTLOOK ------------------------------ At 500 PM AST (2100 UTC), the center of Hurricane Irma was located near latitude 17.6 North, longitude 49.8 West. Irma is moving toward the west near 14 mph (22 km/h). A westward to west-southwestward motion with some reduction in forward speed is expected through Monday night. On the forecast track, the center of Irma is forecast to approach the northern Leeward Islands late Tuesday. Maximum sustained winds are near 115 mph (185 km/h) with higher gusts. Irma is a category 3 hurricane on the Saffir-Simpson Hurricane Wind Scale. Some strengthening is forecast during the next 48 hours. Hurricane-force winds extend outward up to 35 miles (55 km) from the center and tropical-storm-force winds extend outward up to 140 miles (220 km). The estimated minimum central pressure is 969 mb (28.62 inches). HAZARDS AFFECTING LAND ---------------------- WIND: Hurricane conditions are possible within the watch area by Tuesday night, with tropical storm conditions possible by late Tuesday. NEXT ADVISORY ------------- Next intermediate advisory at 800 PM AST. Next complete advisory at 1100 PM AST. $$ Forecaster Brown