The Meteorological Department issued Bulletin No. 12 warning of heavy to very heavy rain in southern Thailand and advised monitoring areas at risk of flash floods and landslides. The Director-General of the Department of Disaster Prevention and Mitigation (DDPM) stated that recovery in Hat Yai is over 75% complete and assured that this rainfall will not be prolonged as in previous events.
11 Dec 2025 GMT+7Meteorological DepartmentIssued Bulletin No. 12 regarding heavy to very heavy rain in southern Thailand and strong winds in the Gulf of Thailand, stating that from 11 to 13 Dec 2025, southern Thailand will experience increased rainfall with heavy rain in several areas including Prachuap Khiri Khan, Ranong, Phang Nga, Krabi, Trang, and Satun provinces.
Very heavy rain is expected in Chumphon, Surat Thani, Nakhon Si Thammarat, Phatthalung, Songkhla, Pattani, Yala, and Narathiwat provinces. This is due to a low-pressure area in the lower South China Sea moving across the southern tip of Vietnam, the Gulf of Thailand, and southern Thailand. From 14 to 16 Dec 2025, the lower south will continue to experience heavy rain in Surat Thani, Nakhon Si Thammarat, Phatthalung, Songkhla, Pattani, Yala, Narathiwat, Krabi, Trang, and Satun due to a strengthening northeast monsoon covering the Gulf of Thailand and the south.
Wave conditions in the Gulf of Thailand and the Andaman Sea will strengthen. In the lower Gulf of Thailand, waves will be 2-3 meters high, exceeding 3 meters in thunderstorms. The upper Gulf of Thailand will have waves about 2 meters high. In the Andaman Sea offshore, waves will exceed 2 meters, rising above 2 meters during thunderstorms.
Residents are advised to beware of dangers from heavy to very heavy rain and accumulated rainfall, which may cause flash floods and sudden torrents, especially near foothills close to waterways and low-lying areas. Mariners in the Gulf of Thailand and Andaman Sea should navigate cautiously and avoid sailing during thunderstorms.
Mariners in the lower Gulf of Thailand should refrain from setting out. Meanwhile, northern Thailand will experience unstable weather with isolated thunderstorms between 11 and 13 Dec 2025 due to easterly winds bringing moisture. Temperatures will then drop 2-4 degrees Celsius, bringing cool to cold weather with strong winds. This is due to a strong high-pressure cold air mass from China covering Thailand. Citizens are advised to take care of their health amid changing weather, and farmers should prepare to protect crops from potential damage.
. The Office of National Water ResourcesHas issued a flood watch for flash floods and urban flooding in southern Thailand from 11 to 15 Dec 2025. Due to the northeast monsoon covering the Gulf of Thailand, the south, and the Andaman Sea, combined with easterly winds over the Gulf and south, rainfall will increase with heavy rain in some areas. Authorities urge vigilance in areas prone to flash floods, landslides, urban flooding due to drainage overflow, and riverbank overflow in low-lying areas from 11 to 15 Dec 2025 in Nakhon Si Thammarat, Phatthalung, Songkhla, Trang, Pattani, Yala, and Narathiwat provinces. The flash flood risk areas are as follows:
Meanwhile, Mr. Theerapat Kachamat, Director-General of the Department of Disaster Prevention and Mitigation, spoke about preparedness for heavy to very heavy rain from 11 to 16 Dec 2025. He said meteorological agencies predict heavy to very heavy rain in southern Thailand, especially on 11-12 Dec in Chumphon, Surat Thani, and Nakhon Si Thammarat provinces. Phatthalung and upper Songkhla will experience moderate to heavy rain. Songkhla is expected to have heavy rain from 13 to 16 Dec. After 14 Dec, the rain will shift toward the lower south in Yala, Pattani, and Narathiwat provinces.
The rainfall during this period will consist of moving rain clusters rather than prolonged rainfall as in previous events, so severe flooding is unlikely. However, minor waterlogging may occur in some areas due to clogged drainage from debris. Songkhla province has prepared by activating the district disaster prevention and mitigation command center to manage the situation, with clear emergency and evacuation plans, zoning, and assigned responsibilities to assist residents quickly and minimize inconvenience.
"Regarding public warnings, the Department of Disaster Prevention and Mitigation and related agencies will use meteorological data to assess and analyze the situation, sending alerts via Cell Broadcast to residents in risk areas. To maximize warning effectiveness, if provinces identify risks threatening residents, they should coordinate with the Department to immediately send alert messages," emphasized Mr. Theerapat, Director-General of DDPM.