Vietnam: Adverse weather forecast across central and southern regions through at least Dec. 9 /update 2

Event

Thunderstorms, strong winds, landslides, and flooding are forecast across southern and central Vietnam through at least Dec. 9. The Vietnam National Center for Hydro-Meteorological Forecasting (NCHMF) has warned of moderate to very heavy rain across the affected area through at least Nov. 30, with 10-25 cm (4-10 inches) of rainfall forecast in Quang Nam, Quang Ngai, and Binh Dinh provinces and 5-8 cm (2-3 inches) in Thua Thien Hue, Da Nang, Phu Yen, Khanh Hoa, and Ninh Thuan provinces, as well as across the Central Highlands.

The NCHMF has issued a level 2 warning of natural disaster risk due to heavy rain, tornadoes, lightning, and hail for Quang Nam, Quang Ngai, and Binh Dinh provinces and a level 1 warning for Thua Thien Hue, Da Nang, Phu Yen, Khanh Hoa, and Ninh Thuan provinces, as well as across the Central Highlands. The NCHMF has also warned of possible flash floods, landslides in mountainous terrain, and floods in low-lying areas. Officials could update and possibly extend the coverage of weather alerts over the coming days. Forecast models indicate that the heavy rainfall and thunderstorms are likely to continue through at least Dec. 9.

Reports indicate that flooding is occurring along the Tra Khuc and Ve rivers in Quang Ngai province and the Kon River in Binh Dinh province, with further flooding forecast for other rivers across the affected area.

Hazardous Conditions
Sustained heavy rainfall could trigger flooding in low-lying communities near rivers, streams, and creeks. Urban flooding is also possible in developed areas with easily overwhelmed or a lack of stormwater drainage systems. Sites located downstream from large reservoirs or rivers may be subject to flash flooding after relatively short periods of intense rainfall. Landslides are possible in hilly or mountainous areas, especially where the soil has become saturated by heavy rainfall. Disruptions to electricity and telecommunications services are possible where significant flooding, strong winds, or landslides impact utility networks.

Transport
Floodwaters and debris flows may render some bridges, rail networks, or roadways impassable, impacting overland travel in and around affected areas. Ponding on road surfaces could cause hazardous driving conditions on regional highways. Authorities could temporarily close some low-lying routes that become inundated by floodwaters. Flooding and landslides caused by heavy rainfall have blocked a number of routes in the affected area Nov. 29. In Quang Nam province, sections of the National Highway 40B are flooded and several other roads are closed due to flooding and landslides. Several roads in the Tra Bong River basin, Binh Son District, in Quang Ngai Province have also been affected by flooding.

Severe weather could also trigger flight delays and cancellations at regional airports. Authorities may temporarily suspend port operations or close beach fronts along the Gulf of Thailand and the South China Sea if strong winds trigger hazardous sea conditions. Flooding could block regional rail lines; freight and passenger train delays and cancellations are likely in areas that see heavy rainfall and potential track inundation.

Localized business disruptions may occur in low-lying areas; some businesses might not operate at full capacity because of flood damage to facilities and some employees' inability to reach work sites.

Advice

Monitor local media for weather updates and related advisories. Confirm all transport reservations and business appointments before travel. Make allowances for localized travel delays and potential supply chain disruptions where flooding has been forecast. Do not drive on flooded roads. Charge battery-powered devices in the case of prolonged electricity outages.

Resources

Vietnam National Centre for Hydro-Meteorological Forecasting (Vietnamese)