Indian Ocean: Tropical Cyclone Dumako forms, tracking west-southwestwards in the Indian Ocean early Feb. 14

Event

Tropical Cyclone Dumako has formed and is tracking west-southwestwards in the Indian Ocean early Feb. 14. As of 00:001 EAT, the storm's center of circulation was approximately 500 km (310 miles) north-northeast of Port Louis, Mauritius. Forecast models indicate the system will track generally westwards while strengthening temporarily through late Feb. 14 before weakening slightly and making landfall as a moderate tropical storm over Sava or Analanjirofo region, Madagascar, late Feb. 15. Dumako is then likely to weaken rapidly as it tracks west-northwestwards across northern Madagascar and exits into the Mozambique Channel late Feb. 16. Some uncertainty remains in the track and intensity forecast, and changes could occur in the coming days.

As of early Feb. 14, the Madagascar General Directorate of Meteorology has warned heavy rain of more than 10 cm (4 inches) is likely around the landfall area. Green (lowest level on a four-tier scale) alerts are in place for Diana, Sava, and Analanjirofo regions as well as Brickaville, Toamasina I, and Toamasina II districts. People between Brickaville and Vohemar are advised not to go out to sea from the evening of Feb. 14 as weather conditions are likely to deteriorate. A yellow heavy swell vigilance is in place along the central and northeast coasts. Authorities will likely issue new warnings or update existing advisories throughout the system's progression in the coming days.

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 airports in the region, such as Ivato International Airport (TNR), Fascene Airport (NOS), and Sainte Marie Airport (SMS), and temporary closures of ports are also possible. Stagnant pools of water during and after flooding increase 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

Joint Typhoon Warning Center
Madagascar General Directorate of Meteorology (French)