091 WTNT34 KNHC 142048 TCPAT4 BULLETIN Tropical Storm Isaac Advisory Number 29 NWS National Hurricane Center Miami FL AL092018 500 PM AST Fri Sep 14 2018 ...ISAAC BECOMES A TROPICAL STORM AGAIN BUT ITS FUTURE IS UNCLEAR... SUMMARY OF 500 PM AST...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...15.3N 68.2W ABOUT 250 MI...400 KM SSE OF SANTO DOMINGO DOMINICAN REPUBLIC ABOUT 600 MI...965 KM ESE OF KINGSTON JAMAICA MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H PRESENT MOVEMENT...W OR 275 DEGREES AT 14 MPH...22 KM/H MINIMUM CENTRAL PRESSURE...1002 MB...29.59 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. Interests in Jamaica should monitor the progress of Isaac. DISCUSSION AND OUTLOOK ---------------------- At 500 PM AST (2100 UTC), the center of Tropical Storm Isaac was located near latitude 15.3 North, longitude 68.2 West. Isaac is moving toward the west near 14 mph (22 km/h), and this general motion with some decrease in forward speed is anticipated over the next couple of days with a turn to the west-northwest possible by late Sunday. On the forecast track, Isaac will move over the eastern and central Caribbean Sea during the next few days, and be near or south of Jamaica early next week. NOAA Hurricane Hunter data indicate that maximum sustained winds have increased to near 40 mph (65 km/h) with higher gusts. Little change in strength is forecast during the next 36 hours. Isaac is forecast to become a tropical depression on Sunday and degenerate into a wave on Monday. However this is an uncertain prediction. Tropical-storm-force winds extend outward up to 45 miles (75 km) from the center. The estimated minimum central pressure from dropsonde data is 1002 mb (29.59 inches). HAZARDS AFFECTING LAND ---------------------- RAINFALL: Isaac is expected to produce additional rainfall of 2 to 3 inches with isolated maximum totals of up to 5 inches across southeast Puerto Rico. Rainfall totals of 1 to 2 inches with maximum amounts of 3 inches are possible across the remainder of Puerto Rico, the Virgin Islands, the Leeward Islands and the northern Windward Islands. Rainfall totals of 2 to 3 inches with isolated maximum amounts of 4 inches are possible across the south- central portion of the Dominican Republic, southwest Haiti and most of Jamaica except for the eastern portion of Jamaica where rainfall totals of 2 to 4 inches and maximum amounts of 6 inches are possible. This rainfall may cause life-threatening flash floods. NEXT ADVISORY ------------- Next complete advisory at 1100 PM AST. $$ Forecaster Blake