North Atlantic Ocean: Potential Tropical Cyclone 16 tracking northwards off the southeast coast the US as of Sept. 21

Event

A low-pressure system with the potential for cyclonic development named Potential Tropical Cyclone 16 is tracking northward in the North Atlantic Ocean off the southeast coast of the US on Sept. 21. As of 11:00 EDT, the system's center of circulation was approximately 725 km (450 miles) southeast of Charleston, South Carolina.

Forecast models indicate that the system will strengthen but remain a subtropical storm as it tracks generally northward through early Sept. 22. The system is then expected to transition into a tropical storm before turning to track north-northwestward late Sept. 22 and making landfall north of Morehead City, North Carolina, early Sept. 23. The storm is forecast to initially maintain tropical storm strength as it tracks northward over eastern North Carolina and eastern Virginia Sept. 23, before weakening into a tropical depression as it tracks north-northeastward and then northeastward over Chesapeake Bay, Maryland, and Delaware through Sept. 24. The system is expected to exit the east coast over southern New Jersey Sept. 24 and head back out into the North Atlantic Ocean. Some uncertainty remains in the track and intensity forecast, and significant changes could occur over the coming days.

As of Sept. 21, officials have issued the following coastal warnings and watches due to the storm system:

• Tropical Storm Warning: Cape Fear, North Carolina, to Fenwick Island, Delaware; Chesapeake Bay south of Smith Point; and Albemarle and Pamlico Sounds, North Carolina.

• Storm Surge Watch: Surf City, North Carolina, to Chincoteague, Virginia; Chesapeake Bay south of Smith Point; and Albemarle and Pamlico Sounds, North Carolina.

Authorities will likely issue new warnings throughout the system's progression in the coming days.

Tropical-storm-force winds are expected to reach areas of North Carolina within the warning area on Sept. 22 and then spread northward through the rest of the warning area late Sept. 22-23. The system is expected to produce rainfall totals of 5-10 cm (2-4 inches), with localized higher amounts of up to 15 cm (6 inches), across parts of the eastern Mid-Atlantic states from North Carolina to New Jersey Sept. 22-24. Storm surge is possible along parts of the east coast and could reach 0.6-1.2 meters (2-4 feet) in the warning area and 0.3-0.9 meters (1-3 feet) in adjacent coastal areas if peak surge occurs during high tide. Swells generated by the system are expected to affect much of the east coast of the US through Sept. 24; these swells are likely to produce life-threatening surf and rip current conditions.

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