1. Dorian is expected to bring tropical storm conditions to portions of the Lesser Antilles through Tuesday morning, where tropical storm watches and warnings are in effect. Rainfall of 3 to 8 inches is expected from Martinique to St. Vincent, including Barbados, with isolated totals as high as 10 inches possible.

2. Tropical storm conditions are possible in Puerto Rico on Wednesday, where a tropical storm watch has been issued. Rainfall of 2 to 4 inches with maximum totals of 6 inches are possible across Puerto Rico and St. Croix.

3. Watches will likely be issued for portions of Hispaniola early Tuesday, as the threat of wind and rain impacts continues to increase.

4. While uncertainty is high, wind and rain impacts are possible in the Bahamas and Florida later this week and this weekend. Residents in these areas should monitor the progress of Dorian and ensure that they have their hurricane plan in place.

WHAT'S NEW:

None.

SUMMARY OF ALERTS:

A Hurricane Watch is in effect for...
- Northwestern Bahamas

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 tropicalstormforce winds, conditions that make outside preparations difficult or dangerous. Interests in southern and central Florida should monitor the progress of Dorian. For storm information specific to your area, please monitor products issued by your national meteorological service.

WIND: [TOP] Hurricane conditions are possible within the watch area by Sunday, with tropical storm conditions possible by Saturday night or Sunday morning.

STORM SURGE: [TOP] A life-threatening storm surge will raise water levels by as much as 10 to 15 feet above normal tide levels in areas of onshore winds in the northwestern Bahamas. Near the coast,the surge will be accompanied by large and destructive waves.

RAINFALL: Dorian is expected to produce the following rainfall accumulations this weekend into the middle of next week:

Northwestern Bahamas and coastal sections of the Southeast United States...6 to 12 inches, isolated 15 inches. Central Bahamas...1 to 2 inches, isolated 4 inches.

This rainfall may cause life-threatening flash floods.

SURF: [TOP] Swells are likely to begin affecting the east-facing shores of the Bahamas and the southeastern United States coast during the next few days. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office.

At 800 AM AST (1200 UTC), the center of Hurricane Dorian was located near latitude 24.2 North, longitude 69.4 West. Dorian is moving toward the northwest near 12 mph (19 km/h), and this motion is expected to continue through today. A slower west-northwestward to westward motion is forecast to begin tonight and continue through the weekend. On this track, Dorian should move over the Atlantic well east of the southeastern and central Bahamas today, approach the northwestern Bahamas Saturday, and move near or over portions of the northwestern Bahamas on Sunday.

Data from an Air Force Reserve reconnaissance aircraft indicate that maximum sustained winds have increased to near 110 mph (175 km/h) with higher gusts. Strengthening is forecast during the next few days, and Dorian is expected to become a major hurricane later today. Dorian is likely to remain an extremely dangerous hurricane while it moves near the northwestern Bahamas and approaches the Florida peninsula through the weekend.

Hurricane-force winds extend outward up to 25 miles (35 km) from the center, and tropical-storm-force winds extend outward up to 105 miles (165 km).

The minimum central pressure just reported by the Air Force reconnaissance plane was 972 mb (28.70 inches).

An Air Force Reserve Unit Hurricane Hunter aircraft has been investigating Dorian this evening. Data from the plane indicate that the storm is not quite as strong as previously estimated, and based on flight-level winds and SFMR-observed surface winds the intensity is set at 45 kt. Fixes from the aircraft show that the center of the cyclone moved just south of the southern coast of Barbados within the last couple of hours, and tropical-storm-force winds were reported over that island. There is fairly well-defined upper-level outflow over the eastern semicircle of the circulation. Although some dry mid-level air is likely to continue to affect Dorian while it moves over the northeastern Caribbean, the dynamical guidance indicates that the shear will not become very strong. Therefore it is still expected that the cyclone will become a hurricane in a couple of days. Some disruption of the system will likely occur when the center moves near eastern Hispaniola. The official intensity forecast is on the high end of the model guidance and is subject to considerable uncertainty, particularly from days 3 to 5.

Dorian continues to move west-northwestward, or 290/11 kt, while being steered by the flow on the south side of the subtropical ridge. In a day or two, the tropical cyclone is expected to turn northwestward due to a weakness in the ridge. The ridge is expected to build somewhat later in the forecast period, which should cause Dorian to turn slightly to the left. The ECMWF model is near the northern side of the guidance suite and the UKMET is near the southern side. The GFS model continues to practically dissipate the system so it was unable to generate a forecast track. The official track forecast was shifted a bit to the north, but lies south of the latest dynamical model consensus. It is advisable that one not focus on small changes in the forecast track due to uncertainties.