1. Tropical storm conditions are expected across portions of the Dominican Republic and Haiti, the Turks and Caicos, the southeastern Bahamas, and Cuba through Monday. Heavy rainfall is likely across these areas and could cause mudslides and flash and urban flooding.

2. Tropical storm conditions are possible the central Bahamas and Andros Island tonight and Monday, and in the Florida Keys on Monday.

3. The details of the long-range track and intensity forecastsremain uncertain since Laura is forecast to move near or overportions of the Greater Antilles through Monday. However, Laura isforecast to strengthen over the Gulf of Mexico and could bring stormsurge, rainfall, and wind impacts to portions of the U.S. Gulf Coastby the middle of next week. This could result in a prolonged periodof hazardous weather for areas that are likely to be affected byTropical Storm Marco earlier in the week. Interests there shouldmonitor the progress of Laura and Marco and updates to the forecastduring the next few days.

EXTENDED WESTWARD ACROSS CUBA...

SUMMARY OF 500 AM EDT...0900 UTC...INFORMATION LOCATION...18.8N 70.9W ABOUT 95 MI...150 KM E OF PORT AU PRINCE HAITI ABOUT 110 MI...175 KM SE OF CAP HAITIEN HAITI MAXIMUM SUSTAINED WINDS...45 MPH...75 KM/H PRESENT MOVEMENT...WNW OR 285 DEGREES AT 18 MPH...30 KM/H MINIMUM CENTRAL PRESSURE...1005 MB...29.68 INCHES

WATCHES AND WARNINGS CHANGES WITH THIS ADVISORY:

The government of Cuba has issued a Tropical Storm Warning for the Cuban provinces of Ciego De Avila, Sancti Spiritus, Villa Clara, Cienfuegos, Matanzas, Mayabeque, La Habana, and Artemisa.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Tropical Storm Warning is in effect for...
- The northern coast of the Dominican Republic from Cabo Engano to the border with Haiti
- The southern coast of the Dominican Republic from Cabo Engano to Punta Palenque
- The northern coast of Haiti from Le Mole St. Nicholas to the border with the Dominican Republic
- The southeastern Bahamas and the Turks and Caicos Islands
- Cuban provinces of Camaguey, Las Tunas, Holguin, Guantanamo, Santiago de Cuba, Granma, Ciego De Avila, Sancti Spiritus, Villa Clara, Cienfuegos, Matanzas, Mayabeque, La Habana, and Artemisa

A Tropical Storm Watch is in effect for...
- The central Bahamas
- Andros Island
- Florida Keys from Ocean Reef to Key West and the Dry Tortugas
- Florida Bay
- Cuban province of Pinar Del Rio

A Tropical Storm Warning for the Dominican Republic and Haiti means that tropical storm conditions are expected somewhere within the warning area today. The Tropical Storm Warning for the Cuban provinces means that tropical storm conditions are expected somewhere within the warning area during the next 24 to 36 hours.

A Tropical Storm Watch means that tropical storm conditions are possible within the watch area, generally within 48 hours.

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.

RAINFALL: Laura is expected to produce the following rainfall accumulations through Tuesday:

Laura is expected to produce the following rainfall accumulations through Tuesday:

Dominican Republic, Haiti and Cuba: 4 to 8 inches, with maximum amounts of 12 inches.

This heavy rainfall could lead to lifethreatening flash and urban flooding, and the potential for mudslides across the Greater Antilles.

Rainfall amounts of 1 to 3 inches, with isolated maximum totals of 5 inches, is expected over the Turks and Caicos, southeast Bahamas, and Jamaica.

Rainfall amounts of 1 to 3 inches is expected across the Florida Keys.

WIND: Tropical storm conditions are expected within portions of the warning area for the Dominican Republic and Haiti through tonight. Tropical storm conditions are expected within portions of the warning area for Cuba this afternoon through Monday. Tropical storm conditions are possible within portions of the watch area tonight through Monday evening.

SURF: Swells generated by Laura are affecting portions of the Virgin Islands, Puerto Rico, and Hispaniola. These swells are expected to spread across Cuba, much of the Bahamas, and the Florida Keys during the next few days. Please consult products from your local weather office.

At 500 AM EDT (0900 UTC), the center of Tropical Storm Laura was located near latitude 18.8 North, longitude 70.9 West. Laura is moving toward the westnorthwest near 18 mph (30 km/h), and this general motion is expected over the next few days. On the forecast track, the center of Laura will move across Hispaniola today, be near or over Cuba tonight and Monday, and over the southeastern Gulf of Mexico Monday night and Tuesday.

Maximum sustained winds are near 45 mph (75 km/h) with higher gusts. No significant changes in strength are forecast during the next 36 to 48 hours while Laura moves over or near Hispaniola and Cuba. Strengthening is forecast once Laura moves into the Gulf of Mexico Monday night and Tuesday.

Tropicalstormforce winds extend outward up to 140 miles (220 km) from the center.

The estimated minimum central pressure based on nearby surface observations is 1005 mb (29.68 inches).

Laura has maintained an impressive convective pattern despite the center being located over extreme south-central Dominican Republic. Numerous cloud tops of -85C to -90C have been noted over the Barahona peninsula, an indication that extremely heavy rainfall has been occurring there. The center of Laura passed over or very near Santo Domingo around 0430Z based on a noticeable wind shift that was measured at the international airport. Laura's outflow pattern has also continue to improve in all quadrants. The initial intensity of 40 kt is based on earlier scatterometer and aircraft data, along with surface observations along the north coast of the Dominican Republic.

Laura has continued to move west-northwestward and the initial motion estimate is now 285/16 kt. There has been a significant westward shift in the latest NHC model guidance, which appears to be due to most of the global models taking the center of Laura farther south over central or southern Hispaniola rather than emerging it off the north coast of Haiti like the GFS is and has been forecasting. Given that the most intense convection has persisted along the southern coast of Hispaniola, that is where the most likely area that a low-level and/or mid-level circulation is most probable to develop or persist. As a result, the new NHC track forecast favors a more southerly and westerly track solution similar to the preponderance of the track guidance. However, the new forecast track has not been shifted as far to the left as the consensus models in the event that the models shift back to the north. However, the latter scenario is appearing less likely based observed satellite trends since the previous advisory.

Little if any significant change in strength is expected due to Laura moving pretty much down the spine of Hispaniola and Cuba during the the next 36 hours, with the strongest wind likely remaining over water in the northeast quadrant where the pressure gradient will be the tightest between the cyclone and the Bermuda High. By 48 hours and continuing until landfall, Laura is forecast to remain in a low shear and very favorable upper-level outflow environment while passing of extremely warm SSTs near 31C. This should allow for significant strengthening to occur once the cyclone regains a decent inner core after exiting Cuba. The new NHC intensity forecast is a blend of the intensity forecasts by the GFS and ECMWF global models and the corrected consensus models HCCA and FSSE.