August 21, 20121307Views

Current Location: 15.2N 52.4W

Geographic Reference: 590 miles east of Dominica

Movement: West at 20 mph

Max Winds: 35 mph gusting to 45 mph

Organizational Trend: Increasing slowly

Forecast Confidence: Average

Current Hurricane Severity Index: 1 (0 size / 1 intensity)

Peak Forecast Hurricane Severity Index: 8 (3 size / 5 intensity)

Changes from Previous Forecast

Forecasters are now indicating that the depression will reach hurricane intensity when it passes south of the Dominican Republic on Thursday evening.

Our Forecast

Tropical Disturbance 37 has been upgraded to Tropical Depression Nine by the National Hurricane Center. Satellite imagery and surface observations indicate that showers and thunderstorms have increased and the circulation is well-defined, which makes Nine at least a tropical depression and possibly a weak tropical storm. A recon plane is scheduled to investigate the depression this afternoon. Forecasters think it is quite likely that the depression will be upgraded to a tropical storm at that time, if not sooner. Its name would be Isaac.

The track models are in fairly good agreement through 5 days. A ridge of high pressure to the north will keep the depression moving west for the next couple of days. A turn to the northwest is expected late in the forecast period. By Saturday, this system will be near the south coast of Cuba. Most of the computer models turn the cyclone to the north-northwest or north over central or western Cuba. Beyond day 5, it is too early to determine if the storm will track just west of the Florida Peninsula, over the Florida Peninsula or east of Florida. Forecasters cannot rule out a possible threat to the central or northwest Gulf coast, though a Florida impact does look most likely at this time.

The intensity forecast beyond 3 days is somewhat uncertain due to potential land interaction with Hispaniola and Cuba. If the cyclone stays south of Hispaniola and then crosses Cuba on the central or western part of the island, it would only weaken slightly due to land interaction. The present forecast takes the system to hurricane strength south of the Dominican Republic on Thursday evening. It should weaken, perhaps significantly, as it crosses Cuba, but it could regain hurricane intensity north of Cuba next Monday.

Expected Impacts on Land

Lesser Antilles including St. Lucia: The first squalls from the system are likely to move through the area late tonight or early Wednesday and last through early Thursday. Tropical storm force winds and heavy rain are possible for the Leeward Islands, from Dominica through Anguilla. In Martinique and St. Lucia, winds are likely to remain well below tropical storm intensity. However, some squalls may occur Wednesday through early Thursday with gusts to 50 mph. The southernmost squalls may extend as far south as Trinidad.

Virgin Islands and Puerto Rico: Occasional heavy squalls are expected to begin Wednesday afternoon and continue through late Thursday. Wind gusts of 55 mph to 65 mph possible in the heavier squalls.

Dominican Republic: Tropical Storm conditions are likely and hurricane conditions are possible for the southern coast late Thursday and early Friday. Heavy rainfall is likely throughout the island of Hispaniola.

Expected Impacts Offshore

Eastern Caribbean: Tropical storm force winds are likely for the eastern Caribbean Sea Wednesday evening through Thursday.


The Department of Disaster Management is monitoring the current system and will provide updates when necessary. Residents are encouraged to make the necessary preparations as the system is forecast to cause Tropical Storm conditions in the territory. Please visit the DDM’s website at and subscribe for future updates.

Disclaimer: The Department of Disaster Management (DDM) is not an official Meteorological Office. The Information disseminated by the Department is gathered from a number of professional sources used or contracted by the DDM to provide such information. This information is to be used as a guide by anyone who has interest in local weather conditions. By no means can the DDM or the BVI Government be held accountable by anyone who uses this information appropriately for legal evidence or in justification of any decision which may result in the loss of finances, property or life.