Thailand issues cold-weather and severe monsoon warning as south braces for heavy floods

Thailand’s Meteorological Department (TMD) has issued Warning No. 12 (351/2568) on cold weather over upper Thailand, heavy to very heavy rain across the south and strong winds over the Gulf of Thailand, with impacts expected through November 23, 2025.

Cold surge over northern and northeastern regions

From November 20–21 , a strong high-pressure system from China has spread over upper Thailand, bringing cold to very cold conditions with strong winds. Temperatures are expected to fall by 1–2°C in the North and Northeast, while the Central region, Bangkok and surrounding areas, and the East will experience cool and windy mornings. Mountain tops and highlands will see cold to very cold weather.

Authorities advise the public to take care of their health during the cold spell and remain cautious of possible fire hazards caused by dry and windy conditions. Farmers are urged to protect crops and agricultural products from damage.

From November 22–23, temperatures over upper Thailand will gradually rise, accompanied by morning fog. However, the North and Northeast will remain cool to cold. The public is urged to drive carefully in fog-prone areas.

Severe monsoon triggers heavy rain and high waves in southern Thailand (Nov 20–23 )

The lower South will face widespread heavy to very heavy rainfall from November 20–23, triggered by a strong northeasterly monsoon covering the Gulf of Thailand, southern provinces and the Andaman Sea, combined with a low-pressure cell over the lower Gulf and southern region.

Waves in the Gulf of Thailand are expected to reach 2–3 metres, exceeding 3 metres in thunderstorms. The upper Andaman Sea will see waves around 2 metres, and 2–3 metres offshore, with even higher waves in stormy zones.

The public in southern provinces is urged to beware of flash floods, run-off and accumulated rain, especially in foothill areas, river channels and lowlands.

Residents along the eastern coast should watch for strong waves hitting the shore.

All vessels in the Gulf of Thailand and Andaman Sea should proceed with caution and avoid sailing during storms. Small boats in the Gulf and offshore Andaman should remain ashore from November 20–23.

TMD urges constant monitoring

The public is advised to follow updates from the Thai Meteorological Department via its website or hotline 1182, available 24 hours.

The announcement was issued on November 20, 2025 at 17:00, with the next update scheduled for 05:00 on November 21, 2025.

Regional Forecast (18:00 today – 18:00 tomorrow)

Northern Region

• Cold to very cold with temperatures dropping 1–2°C.
• Lows 14–18°C, highs 23–29°C.
• Mountain tops: 3–11°C.
• Northeasterly winds 10–20 km/h.

Northeastern Region

• Cold to very cold with strong winds, temperatures down 1–2°C.
• Lows 15–18°C, highs 27–28°C.
• Mountain tops 6–12°C.
• Northeasterly winds 15–35 km/h.

Central Region

• Cool and windy.
• Lows 19–21°C, highs 28–29°C.
• Northeasterly winds 10–30 km/h.

Bangkok and Metropolitan Area

• Cool mornings with strong winds; light rain in some areas.
• Lows 20–22°C, highs 29–31°C.
• Northeasterly winds 10–30 km/h.

Eastern Region

• Cool mornings with strong winds; 20% chance of rain, mostly in Chanthaburi and Trat.
• Lows 19–22°C, highs 28–30°C.
• Winds 20–40 km/h; waves 1–2 m, over 2 m offshore.

Southern Region (East Coast)

• Thunderstorms over 80% of the area, heavy to very heavy rain in Chumphon, Surat Thani, Nakhon Si Thammarat, Phatthalung, Songkhla, Pattani, Yala and Narathiwat.
• Lows 20–24°C, highs 27–28°C.
• Winds 20–40 km/h; waves 2–3 m, above 3 m in storms.

Southern Region (West Coast)

Thunderstorms over 80% of the area, heavy to very heavy in Ranong, Phang Nga, Phuket, Krabi, Trang and Satun.
– Krabi northwards: Winds 20–40 km/h, waves ~2 m, offshore 2–3 m, above 3 m in storms.
– Trang southwards: Winds 20–35 km/h, waves 1–2 m, higher in storms.