Indian Ocean: Severe Tropical Storm Bheki tracking south-southwestward toward the Mascarene Islands Nov. 19 /update 1

Severe Tropical Storm Bheki is tracking south-southwestward in the western Indian Ocean toward the Mascarene Islands Nov. 19. As of 13:00 MUT, the storm's center of circulation was approximately 1,045 km (649 miles) east of Port Louis, Mauritius.

Forecast models indicate the system will weaken slightly as it continues to track generally south-southwestward across the western Indian Ocean and passes to the north of Rodrigues Island, Mauritius, early Nov. 20. Bheki is expected to weaken into a moderate tropical storm and will gradually start to track in a more southwestward trajectory as it passes just south of Mauritius main island early Nov. 21 and then to the southeast of Reunion during the afternoon Nov. 21. The system will weaken further into a tropical depression and then a zone of disturbed weather as it tracks southwestward away from the Mascarene Islands Nov. 22. Some uncertainty remains in the track and intensity forecast; significant changes could occur in the coming days.

As of Nov. 19, the Mauritius Meteorological Service has issued a class three (out of four) cyclone warning for Rodrigues Island and a class one warning for Mauritius Island. Winds and rainfall are expected to intensify gradually, and seas will become increasingly rough as the storm system approaches the islands in the coming days. Meteo France La Reunion has yet to issue any warnings regarding Bheki. Officials will likely issue new alerts or update/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.