Southern Thailand to face 6 days of heavy rain, 8 provinces at risk of over 200 mm rainfall
ONWR warns of severe rainfall across southern provinces from November 18-23, with over 200 mm expected in eight high-risk areas and heightened threats of flash floods and landslides.
The Office of the National Water Resources (ONWR) issued an urgent alert on Tuesday, warning that southern Thailand is set to face six consecutive days of heavy to very heavy rainfall from November 18-23, 2025.
Joint assessments by ONWR, the Thai Meteorological Department, and the Hydro-Informatics Institute show that rainfall will intensify due to a fairly strong northeast monsoon covering the upper Gulf of Thailand and the upper South, combined with easterly wind waves moving across the region. Wind and wave conditions in both the Gulf of Thailand and the Andaman Sea are also expected to strengthen.
Three-day advance forecasts (Nov 18-20) indicate that parts of the following provinces may see over 200 mm of cumulative rainfall:
- Narathiwat
- Yala
- Satun
- Songkhla
- Phatthalung
- Nakhon Si Thammarat
- Surat Thani
- Chumphon
ONWR warned that these areas face a significant risk of flash floods, runoff, and landslides, especially in steep terrain, near waterways, and in low-lying flood-prone zones.
Paithoon Kengkarnchang, ONWR deputy secretary-general, said that water management in the South is particularly challenging due to the region’s diverse geography and exposure to multiple weather systems — the southwest monsoon, northeast monsoon, and tropical cyclones. These factors create overlapping risks of sudden flash floods, mountain runoff, and urban flooding.
He emphasised that ONWR is adopting a proactive preparedness approach, focusing on integrated cooperation between government agencies, the private sector, and local communities to reduce impacts on high-risk populations.
“Effective coordination among all sectors is essential to prevent and mitigate the effects of severe weather on southern communities,” Paithoon said.
Residents are urged to stay alert, follow local warnings closely, and prepare for potential emergency conditions in the coming days.
