000 WTNT32 KNHC 171158 TCPAT2 BULLETIN Tropical Storm Grace Intermediate Advisory Number 16A NWS National Hurricane Center Miami FL AL072021 800 AM EDT Tue Aug 17 2021 ...GRACE NEARING JAMAICA... ...HEAVY RAINS CAUSING FLOODING ACROSS PORTIONS OF HISPANIOLA... SUMMARY OF 800 AM EDT...1200 UTC...INFORMATION ---------------------------------------------- LOCATION...18.2N 76.1W ABOUT 120 MI...195 KM E OF MONTEGO BAY JAMAICA ABOUT 340 MI...550 KM ESE OF GRAND CAYMAN MAXIMUM SUSTAINED WINDS...45 MPH...75 KM/H PRESENT MOVEMENT...W OR 280 DEGREES AT 16 MPH...26 KM/H MINIMUM CENTRAL PRESSURE...1005 MB...29.68 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: The government of Jamaica has changed the Tropical Storm Watch for Jamaica to a Tropical Storm Warning for Jamaica. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Hurricane Watch is in effect for... * Yucatan Peninsula of Mexico from Cabo Catoche to Punta Allen A Tropical Storm Warning is in effect for... * Jamaica * Southern coast of the Cuban provinces of Santiago de Cuba, Granma, Las Tunas, and Camaguey * Cayman Islands A Tropical Storm Watch is in effect for... * Entire coast of Haiti * Southern coast of the Cuban provinces of Ciego de Avila, Sancti Spiritus, Cienfuegos, Matanzas, and Pinar del Rio, as well as Isla de la Juventud. 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 Yucatan Peninsula of Mexico should monitor the progress of Grace. Additional watches or warnings may be required for portions of the Yucatan coast later today. For storm information specific to your area, please monitor products issued by your national meteorological service. DISCUSSION AND OUTLOOK ---------------------- At 800 AM EDT (1200 UTC), the center of Tropical Storm Grace was located near latitude 18.2 North, longitude 76.1 West. Grace is moving toward the west near 16 mph (26 km/h). A general westward to west-northwestward motion is expected for the next several days. On the forecast track, the center of Grace will move near or over Jamaica today. Grace is forecast to move near the Cayman Islands tonight, and then approach the Yucatan peninsula of Mexico late Wednesday or early Thursday. Reports from an Air Force Hurricane Hunter aircraft indicate that the maximum sustained winds are near 45 mph (75 km/h) with higher gusts. Gradual strengthening is forecast during the next couple of days, and Grace could be near hurricane strength when it approaches the Yucatan coast of Mexico late Wednesday and early Thursday Tropical-storm-force winds extend outward up to 45 miles (75 km) from the center. The estimated minimum central pressure is 1005 mb (29.68 inches). HAZARDS AFFECTING LAND ---------------------- Key messages for Grace can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDAT2, WMO header WTNT42 KNHC and on the web at www.hurricanes.gov/graphics_at2.shtml?key_messages. WIND: Tropical storm conditions are expected in portions of Jamaica today. Tropical storm conditions are possible in Haiti early this morning. Tropical storm conditions are expected along the southern coast of Cuba within the warning area this afternoon and evening, and over the Cayman Islands beginning tonight into early Wednesday. Tropical storm conditions are possible along the southern coast of Cuba within the watch area tonight and Wednesday. RAINFALL: Grace is expected to produce the following rainfall amounts: Over Haiti...5 to 10 inches of rain with isolated maximum totals of 15 inches are expected across the southern terrain areas today. This heavy rainfall should lead to flash and urban flooding, and possible mudslides. Over far southern Cuba, Jamaica, the Cayman Islands, and portions of the Yucatan Peninsula....3 to 6 inches of rain with isolated maximum totals of 9 inches are expected through Thursday. This heavy rainfall may lead to flash and urban flooding. SURF: Swells generated by Grace will continue to affect portions of Hispaniola over the next day or so, and will spread westward to Jamaica, the Cayman Islands, the southern coast of Cuba, and the Yucatan Peninsula of Mexico. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. NEXT ADVISORY ------------- Next complete advisory at 1100 AM EDT. $$ Forecaster Pasch