Thailand: Adverse weather forecast across southern provinces through at least Nov. 19

Heavy rainfall is forecast across much of southern Thailand through at least Nov. 19. As of early Nov. 15, the Thai Meteorological Department has issued a weather advisory warning of heavy to very heavy rainfall over southern Thailand, as well as rough seas in the Gulf of Thailand. The heaviest rainfall is forecast over Chumphon, Krabi, Nakhon Si Thammarat, Narathiwat, Pattani, Phang Nga, Phatthalung, Phuket, Prachuap Khiri Khan, Ranong, Songkhla, Surat Thani, and Yala provinces Nov. 16-17 and over Krabi, Nakhon Si Thammarat, Narathiwat, Pattani, Phatthalung, Satun, Songkhla, Surat Thani, Trang, and Yala provinces Nov. 18-19.

The heavy downpours may result in flash floods and landslides in parts of the affected provinces. Rough seas are also forecast in the Gulf of Thailand due to strong winds. Authorities have requested that all vessels navigate with caution and avoid areas with thunderstorms. Small vessels should refrain from leaving the shore Nov. 17-19. Officials could update and possibly extend the coverage of the relevant weather alerts over the coming days.

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 heavy rainfall has saturated the soil. Disruptions to electricity and telecommunications services are possible where significant flooding, landslides, or strong winds impact utility networks.

Floodwaters and debris flows could render some bridges, rail networks, or roadways impassable, impacting overland travel 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.

Severe weather could also trigger intermittent flight delays and cancellations at airports across the affected region, though these are unlikely to be severe or prolonged. Authorities may temporarily suspend port operations or close beach fronts in the Gulf of Thailand if strong winds trigger hazardous sea conditions. Flooding could block regional rail lines; freight and passenger train delays and cancellations are possible in areas that see heavy rainfall and potential track inundation. Localized business disruptions may occur in low-lying areas.

Flooding could heighten the threat of disease outbreaks. Backflow from drains mixed with floodwaters can become trapped in open areas when inundations recede. These stagnant pools often become a breeding ground for mosquitoes and bacteria, increasing the incidence of insect- and water-borne diseases. Exposure to contaminated water from inundated industrial sites, sewer systems, and septic tanks also poses a significant health threat.