Indian Ocean: Tropical Cyclone Dikeledi tracking westward toward northern Madagascar early Jan. 11 /update 1

Tropical Cyclone Dikeledi is tracking westward in the western Indian Ocean toward northern Madagascar early Jan. 11. As of 00:01 EAT, the storm's center of circulation was approximately 824 km (512 miles) north-northwest of Port Louis, Mauritius.

Forecast models indicate the system will strengthen slightly but remain a severe tropical storm as it tracks westward and makes landfall near the border of Diana and Sava regions, Madagascar, late Jan. 11 before exiting into the Mozambique Channel shortly after. Dikeledi is forecast to weaken slightly but remain a severe tropical storm as it turns to track southwestwards and passes south of Mayotte late Jan. 12 before strengthening slightly while turning to track southwards along the coast of western Madagascar and making a close approach to Atsimo-Andrefana Region late Jan. 15. Some uncertainty remains in the track and intensity forecast, and changes may occur in the coming hours and days.

As of early Jan. 11, Meteo Madagascar issued a yellow (middle level on the three-tier scale) cyclone alert; widespread flooding, river flooding, and landslides are likely in the northern part of the country. The storm could generate strong swells of more than 8 meters (26 feet); coastal flooding on the northeast coast is possible. Officials advise maritime users across northern and central Madagascar not to venture out to sea. Authorities also issued red heavy swell warnings between Bobaomby and Mahanoro, yellow heavy rain warnings in Alaotra-Mangoro, Atsinanana, and Analanjirofo regions, yellow strong wind warnings between Antsiranana and Toamasina, yellow heavy swell warnings between Bobaomby and Maintirano, green heavy rain warnings in Melaky Region, green strong wind warnings between Antsiranana and Maintirano, and green heavy swell warnings between Maintirano and Morombe. Officials will likely update or rescind existing advisories as the storm progresses.

Sustained heavy rainfall could trigger flooding in low-lying areas and those with easily overwhelmed drainage systems. Localized evacuations, flash flooding, and landslides are possible. The inclement weather could trigger localized business, transport, and utility disruptions, rendering 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 increase insect- and waterborne diseases, such as dengue fever, cholera, and malaria. Raw sewage and other hazardous materials mixed with floodwaters pose a serious health threat.