11 Jun 2021 | 06:48 PM UTC
South China Sea: Storm 92W in South China Sea likely to bring severe weather to parts of southern China and northern Vietnam through June 14
Storm 92W moving northwest in South China Sea June 12. Severe weather likely in parts of southern China, northern Vietnam through June 14.
Event
A storm designated 92W is tracking west-northwestward in the South China Sea as of early June 12. Meteorologists have classified the system as a monsoon depression, although it may strengthen into a tropical storm in the coming days. The system's track and intensity forecast remain somewhat uncertain, and projections may change accordingly over the coming days.
Government Advisories
As of early June 12, officials in China have warned of heavy rains and potentially damaging winds in parts of Hainan. Vietnamese authorities are forecasting potentially severe weather in the Red River Delta region including Hanoi, along with the provinces of Ha Tinh, Hoa Binh, Nghe An, Phu Tho, Quang Binh, and Thanh Hoa. Weather warnings could remain active even after the system's immediate threat has diminished, as some areas may still be highly susceptible to rain-induced hazards. The possibility of localized evacuations cannot be discounted if weather conditions prove particularly hazardous.
Hazardous Conditions
The storm may bring heavy rainfall, strong winds, and rough seas to coastal areas in its path into at least June 14. Sustained heavy rainfall could trigger flooding in low-lying communities near streams, creeks, rivers, and urban areas with easily overwhelmed stormwater drainage systems. Sites located downstream of large reservoirs could experience flash flooding after relatively short periods of intense rainfall. Rain-induced landslides are possible in steeply sloped terrains. Flooding could isolate some communities for several days. Prolonged swells and storm surge generated by the system will likely result in coastal flooding as the system approaches land. Persistent onshore flow could make it difficult for the surge to recede and for water levels to decrease in coastal river catchments.
Transport
Inclement weather associated with the storm could trigger localized business, transport, and utility disruptions. Floodwaters and debris flows could render some bridges or roadways impassable, impacting overland travel in and around affected areas. Areal flooding in urban locations could also result in severe traffic congestion, while strong winds will pose a hazard to high-profile vehicles. Heavy rain and low visibility may trigger flight disruptions at regional airports.
Disruptions triggered by inclement weather and resultant hazards, such as flooding, could persist well after conditions have improved. If there is severe damage to infrastructure, repair or reconstruction efforts may exacerbate residual disruptions.
Health
Stagnant pools of water during and after flooding increase the incidence of insect- and waterborne diseases, such as dengue fever, cholera, and malaria. The threat of these disease outbreaks is usually elevated in the low-income or underdeveloped areas of major urban centers due to the presence of incomplete or open sewer lines. The latent threat of waterborne contaminants from inundated industrial sites cannot be discounted; 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 severe 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 high 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 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. Keep any necessary medications in a waterproof container.
Plan accordingly for commercial, transport, and logistics disruptions in areas in the path of the storm, especially if 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.
