BANGKOK, THAILAND – Southern provinces faced warnings of extreme rain, flooding and dangerous seas as a deep low-pressure system collided with a strong monsoon.
Deep low and monsoon fuel severe weather
A powerful low-pressure system over the lower South and Malaysia met an equally strong northeast monsoon, creating what forecasters described as an explosive mix. The Thai Meteorological Department (TMD) issued alerts for heavy to extreme rainfall, sudden flash floods and high waves, valid through Tuesday, 25 November 2025. In many communities, tension ran high as one resident in Nakhon Si Thammarat said,
“We are watching every dark cloud – it could start at any moment.”
said a resident, Nakhon Si Thammarat.
Ten southern provinces braced for extreme rain
The TMD expected thunderstorms over 70 to 80 percent of parts of the South, with extreme rainfall likely in ten provinces including Nakhon Si Thammarat, Phatthalung, Songkhla, Pattani, Yala, Narathiwat, Trang and Satun. Low-lying areas and slopes along rivers were considered especially at risk, as water could turn into dangerous flash floods within minutes; meteorologists warned,
“The soil is saturated – every additional minute of rain increases the risk.”
said meteorologists, TMD. Many families prepared sandbags or packed essentials for possible evacuation, while experts cautioned that rivers could overflow overnight.
Coastal regions warned of three-metre waves
On the coast, conditions over the Gulf of Thailand grew increasingly rough, with waves of 2 to 3 metres and potentially higher in storm zones threatening coastal towns and fishing communities. The TMD issued a clear warning, stating,
“Small boats must stay on shore!”
said TMD, national meteorological authority. Fishermen were urged to halt trips at least until Tuesday as coastal villages reinforced for heavy surf that could flood shore roads, and in the Andaman Sea captains were told to avoid storm cells due to the risk of “dangerous, unpredictable seas.”
Frost on Doi Inthanon draws crowds in the north
While the South prepared for flooding, northern Thailand experienced a wintry contrast as the first frost of 2025 formed on Doi Inthanon, the country’s highest peak, on Monday. Tourists flocked to the mountain to witness grasses turning into fine, glittering ice crystals at 5 degrees Celsius on the summit, 4 degrees at Kew Mae Pan and 8 degrees at the park office, with one visitor calling it
“A magical sight.”
said a visitor, tourist. Frost, which occurs when water vapour turns directly to ice, remained a rare spectacle in tropical Thailand, typically appearing only on mountaintops between November and February.
Upper Thailand faces fog and health concerns
In upper Thailand, the cold air mass from China weakened, bringing slightly higher temperatures but denser morning fog. Authorities warned of poor visibility during commuter hours and an increased risk of fires driven by dryness, while a doctor in Chiang Mai cautioned,
“People underestimate the rapid temperature changes.”
said a doctor, Chiang Mai physician. Many residents were considered more vulnerable to colds and respiratory problems, leading officials to recommend warm clothing and caution on all roads.
Next official update due on Tuesday
The next formal bulletin from the TMD was scheduled for Tuesday at 05:00, leaving conditions tense in many parts of the country until then. The South prepared for what could be the heaviest hours of rain as the North remained in winter mode, and questions persisted over whether the weather would calm or another wave of turmoil was already approaching.