Thailand Issues Warning for Tropical Storm Koto, Cooler Weather Expected

TMD Issues Warning for Tropical Storm Koto

The Thai Meteorological Department (TMD) has issued multiple advisories, including Warning No. 7, concerning Tropical Storm Koto. As of November 29, 2025, the storm was situated over the central South China Sea, characterized by maximum sustained winds of approximately 93 km/h. Koto is moving slowly west-southwest and is projected to approach the Vietnamese coastline between November 30 and December 2. Forecasters anticipate a rapid weakening of the storm as it makes landfall in southern Vietnam and eventually dissipates over Cambodia, confirming it will not directly impact Thailand.

Indirect Impacts: Cooler Temperatures and Strong Winds

Despite not making direct landfall, Tropical Storm Koto's presence, coupled with a strong high-pressure system and a cold air mass originating from China, is significantly influencing Thailand's weather patterns. Cooler to cold conditions are now prevalent across upper Thailand and parts of the South.

• The Northeastern region is experiencing the most pronounced temperature drops, with declines of 4 to 7°C.
• The North, Central Region, Bangkok and its vicinity, the East, and the Upper South are seeing temperatures fall by 2 to 4°C.
• Mountain peaks in these regions are forecast to reach lows between 3 and 12°C, with some areas potentially dropping to 5°C.

Accompanying the cooler weather are strong winds and morning fog. The dry air conditions associated with these weather changes have prompted warnings about increased fire risks.

Marine Conditions and Rainfall Outlook

The TMD has also advised caution for marine activities. Moderate to rough seas are expected in the Gulf of Thailand and the Andaman Sea, with waves reaching 1 to 2 meters, and potentially higher in stormy areas. Small boats are urged to proceed with caution or remain in port.

While direct storm impact is not expected, the storm's moisture is anticipated to bring increased rainfall to Thailand's eastern provinces, specifically Rayong, Chanthaburi, and Trat, between December 2 and 3. Additionally, isolated heavy showers are possible in the lower southern provinces, including Pattani, Yala, and Narathiwat. Experts also note a potential interaction between Koto and Tropical Depression Senyar, which could temporarily strengthen Koto before its eventual weakening over Vietnam.

Public Advisory

Residents in affected areas are advised to prepare for the colder conditions, protect their health, and be vigilant against fire hazards. Farmers are encouraged to take measures to safeguard crops susceptible to cold damage. The public is urged to stay informed through official updates from the Thai Meteorological Department.