North Atlantic Ocean: Hurricane Tammy tracking northwestward away from the Leeward Islands as of Oct. 22 /update 5

Event

Hurricane Tammy is tracking northwestward in the North Atlantic Ocean away from the Leeward Islands Oct. 22. As of 11:00 AST, the system's center of circulation was approximately 100 km (60 miles) north of Anguilla.

Forecast models indicate that the storm will maintain Category 1 hurricane strength as it tracks north-northwestward then north-northeastward and northeastward across the Sargasso Sea region of the North Atlantic through Oct. 25. Tammy is then expected to turn north-northeastward and then northwestward Oct. 25-26 and will likely transition into a post-tropical cyclone as it begins to approach Bermuda early Oct. 27. Some uncertainty remains in the track and intensity forecast, and significant changes could occur over the coming days.

As of Oct. 22, authorities have discontinued all coastal watches and warnings.

Further rainfall is expected in parts of the Leeward Islands through at least the remainder of Oct. 22. Storm total rainfall amounts of 10-20 cm (4-8 inches) are expected across the Leeward Islands, an additional 5-10 cm (2-4 inches) across Dominica and Martinique, and 2.5-5 cm (1-2 inches) across the British Virgin Islands, US Virgin Islands, and eastern Puerto Rico. Swells generated by Tammy are forecast to continue to affect portions of the Lesser Antilles over the coming days, likely producing life-threatening surf and rip current conditions.

Some flooding and minor damage have been reported in parts of the Leeward Islands, but no casualties or major disruptions have been confirmed as of Oct. 22; damage assessments are ongoing and it may take some time for the full extent of the storm's impact to be revealed. Several airlines canceled flights across the region Oct. 20-22; however, operations will likely resume in the coming hours as the storm moves away from the region. Lingering delays may occur in the coming days as airlines work to clear the backlog from previous flight disruptions.

Sustained heavy rainfall could trigger flooding in low-lying areas and those with easily overwhelmed drainage systems. If weather conditions prove hazardous, localized evacuations, flash flooding, and landslides are possible.

The inclement weather could trigger localized business, transport, and utility disruptions and render some bridges or roadways impassable. Flight disruptions at regional airports and temporary closures of ports are also possible. Stagnant pools of water during and after flooding may increase the incidence of insect- and waterborne diseases, such as dengue fever, cholera, and malaria. Exposure to raw sewage and other hazardous materials mixed with floodwaters poses a serious health threat.

Advice

Activate contingency plans in areas where officials forecast tropical storm conditions. Heed any evacuation orders that may be issued. Use extreme caution in low-lying coastal areas and near streams, creeks, and other waterways due to the potential for severe flooding and storm surge. Stockpile water, batteries, and other essentials in advance. Charge battery-powered devices when electricity is available; restrict the use of cellular phones to emergencies only. Power down mobile devices when not in use. Keep important documents and necessary medications in waterproof containers. Observe strict food and water precautions, as municipalities could issue boil-water advisories following flooding events. Take precautions against insect- and waterborne diseases in the coming weeks.

Plan accordingly for protracted commercial, transport, and logistics disruptions in areas in the path of the storm, especially if vital infrastructure is damaged. Seek updated information on road conditions before driving or routing shipments through areas where flooding has occurred. Confirm flights before checking out of hotels or driving to the airport; clearing passenger backlogs may take several days in some locations.

Resources

US National Hurricane Center