Bay of Bengal: Tropical Cyclone Mocha tracking north-northeastwards as of early May 13 /update 2

Event

Tropical Cyclone Mocha has intensified and is tracking north-northeastwards across the Bay of Bengal early May 13. As of 03:30 MMT, the storm's center of circulation was approximately 845 km (525 miles) south of Kolkata, India. Forecast models indicate that Mocha will strengthen further through early May 14 before weakening slightly and making landfall over far northwestern Rakhine State in Myanmar the afternoon of May 14. The system is forecast to weaken rapidly as it tracks over western Myanmar through May 15 before dissipating over far western Kachin State early May 16. The storm's track and intensity forecast remain somewhat uncertain, and changes may occur over the coming days.

As of early May 13, the Myanmar Department of Meteorology and Hydrology has warned of rain and thunderstorms across Ayeyarwady, Bago, Magway, Mandalay, Sagaing, Taninthayi, and Yangon regions, Chin, Kachin, Kayah, Kayin, Mon, Rakhine, and Shan states, and Naypyitaw Union Territory through May 15. Regionally heavy rainfall is likely in Ayeyarwady, Bago, Magway, Mandalay, southern Sagaing, and Yangon regions and Chin and Rakhine states, while isolated heavy rainfall is forecast in Naypyitaw Union Territory, northern Sagaing Region, and Kachin, Kayah, Kayin, Mon, and Shan states through May 15. Strong winds and rough to very rough seas are likely off and along the Rakhine State coast through May 14.

The Bangladesh Meteorological Department has warned that the low-lying areas of Chattogram and Cox's Bazar districts, including their offshore islands and chars, will likely be flooded due to storm surges of 2.5-3.5 meters (8-12 feet) above the normal astronomical tide. Low-lying areas of Bhola, Chandpur, Feni, Laxmipur, and Noakhali districts, including their offshore islands and chars, will probably be flooded due to storm surges of 1.5-2 meters (5-7 feet) above the normal astronomical tide. Authorities have advised all fishing vessels in the North Bay to remain in shelter until further notice.

The India Meteorological Department has issued yellow (lowest level on a three-tier scale) thunderstorm warnings across Gangetic West Bengal State and the Andaman and Nicobar Islands and yellow heavy rain warnings over Manipur, Nagaland, and Mizoram states May 13. Orange heavy rain warnings are in place over Manipur, Nagaland, and Mizoram states May 14, while authorities have issued yellow heavy rain warnings over Arunachal Pradesh, Assam, and Meghalaya states and yellow thunderstorm warnings across West Bengal State the same day. Officials will likely issue new alerts or update/rescind existing advisories as the storm progresses.

Reports indicate that authorities are evacuating hundreds of thousands of people in low-lying areas of Bangladesh and Myanmar, including the Ayeyarwady Delta and coastal regions of Myanmar and St Martin's Island in Teknaf, Cox's Bazar, Bangladesh. Authorities have readied around hundreds of cyclone shelters in southeastern Bangladesh, most of them in Chattogram and Cox's Bazar districts. Mocha will likely threaten almost one million Rohingya refugees living in camps in Cox's Bazar District in Bangladesh and Sittwe Township in Rakhine State, Myanmar.

Authorities in Bangladesh suspended river transport from late May 12 and flight operations at Shah Amanat International Airport (CGP) in Chattogram from early May 13. Operations will probably resume after the storm passes and when it is safe.

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 if weather conditions prove hazardous.

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. Severe weather will likely prompt internet and mobile telecommunications disruptions in affected areas; power outages caused by the cyclone may exacerbate service disruptions. 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.

Advice

Activate contingency plans in areas where officials forecast adverse weather 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. 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
India Meteorological Department
Bangladesh Meteorological Department
Myanmar Department of Meteorology and Hydrology