Cooler weather expected in upper Thailand with very heavy rain in South
Small boats in the lower Gulf should stay ashore as waves are forecast to reach 2–3 metres, while the upper North faces thundershowers and gusty winds.
- A high-pressure system from China is bringing cooler weather and strong winds to upper Thailand.
- Heavy to very heavy rain is forecast for southern Thailand from November 11 to 13, with authorities warning of potential flash floods.
- Mariners are being cautioned about strong winds and high waves of 2-3 meters in the Gulf of Thailand and Andaman Sea, with small boats in the lower Gulf advised to stay ashore.
The Thai Meteorological Department issued an advisory on Wednesday (November 11, 2026) for heavy to very heavy rain in southern Thailand, with effects expected to continue until November 13.
Isolated heavy to very heavy rain is forecast in the South over November 11–13.
Residents should be alert to the risk of flash floods and torrents of water from higher ground caused by continuous rainfall and its accumulation, particularly on foothill slopes near waterways and in low-lying areas.
Winds and waves in the Andaman Sea and the Gulf of Thailand are also expected to strengthen.
Waves in the lower Gulf are forecast to reach 2–3 metres, exceeding 3 metres in thundershowers.
Mariners in the Gulf of Thailand and the Andaman Sea should proceed with caution and avoid areas with thundershowers.
Small boats in the lower Gulf should remain ashore during this period.
A high-pressure system, or cold air mass, from China is expected to extend over Thailand, bringing cooler weather and strong winds.
Isolated thundershowers and gusty winds are forecast in the upper North.
People should take care of their health as conditions become colder, while farmers should take precautions against potential damage to agricultural produce.
These conditions are due to a relatively strong high-pressure system, or cold air mass, from China covering upper Thailand and the South China Sea, together with a westerly trough moving across Myanmar and northern Thailand.
Meanwhile, a moderate northeast monsoon is prevailing over the Gulf of Thailand, the South and the Andaman Sea.
The public should plan daily activities and travel carefully during this period to stay safe and minimise potential impacts, and continue following the department’s advisories.
Information is available at tmd.go.th or by calling 0-2399-4012-13 or 1182, 24 hours a day.
The advisory was issued at 5pm on November 11.
The next advisory will be issued at 5am on November 12.
Provinces expected to be affected
11 November
Provinces expected to experience heavy rain:
- South: Chumphon, Surat Thani, Nakhon Si Thammarat, Phatthalung and Songkhla.
November 12
Provinces expected to experience very heavy rain:
- South: Chumphon, Surat Thani and Nakhon Si Thammarat.
Provinces expected to experience heavy rain:
- South: Phatthalung, Songkhla, Pattani, Yala, Narathiwat, Ranong, Phuket, Krabi, Trang and Satun.
November 13
Provinces expected to experience very heavy rain:
- South: Surat Thani and Nakhon Si Thammarat.
Provinces expected to experience heavy rain:
- South: Phetchaburi, Prachuap Khiri Khan, Chumphon, Phatthalung, Songkhla, Pattani, Yala, Narathiwat, Ranong, Phang Nga, Krabi, Trang and Satun.
Thailand weather forecast from 6pm on November 11 to 6pm on November 12
North
- Cool mornings with strong winds and a temperature drop of 1–2°C.
- Thundershowers covering 40% of the region.
- Rain mainly in Mae Hong Son, Chiang Mai, Chiang Rai, Lamphun, Lampang, Phayao and Nan.
- Minimum temperatures: 16–23°C.
- Maximum temperatures: 23–31°C.
- Cold conditions on mountaintops, with minimum temperatures of 9–15°C.
- Northwesterly winds at 10–30 km/h.
Northeast
- Cool mornings with strong winds and isolated light rain in the lower part of the region.
- Minimum temperatures: 17–20°C.
- Maximum temperatures: 28–31°C.
- Cold conditions on mountaintops, with minimum temperatures of 10–14°C.
- Northeasterly winds at 15–30 km/h.
Central region
- Cool mornings with strong winds and isolated light rain.
- Minimum temperatures: 20–23°C.
- Maximum temperatures: 31–33°C.
- Northeasterly winds at 10–30 km/h.
East
- Cool mornings with strong winds and isolated light rain.
- Minimum temperatures: 20–23°C.
- Maximum temperatures: 30–34°C.
- Northeasterly winds at 15–30 km/h.
- Waves about 1 metre high, exceeding 1 metre offshore.
South (east coast)
- Thundershowers covering 60% of the region, with isolated heavy rain.
- Heavy rain in Chumphon, Surat Thani, Nakhon Si Thammarat, Phatthalung and Songkhla.
- Minimum temperatures: 22–24°C. Maximum temperatures: 28–32°C.
- From Surat Thani northwards: northeasterly winds at 15–35 km/h.Waves 1–2 metres high, exceeding 2 metres in thundershowers.
- From Nakhon Si Thammarat southwards: easterly winds at 20–40 km/h.Waves 2–3 metres high, exceeding 3 metres in thundershowers.
South (west coast)
- Thundershowers covering 60% of the region.
- Rain mainly in Ranong, Phang Nga, Trang and Satun.
- Minimum temperatures: 23–25°C. Maximum temperatures: 30–34°C.
- Easterly winds at 15–35 km/h.
- Waves about 1 metre high, rising to 1–2 metres offshore.
- Waves exceeding 2 metres in thundershowers.
Bangkok and surrounding provinces
- Cool mornings with strong winds and isolated light rain.
- Minimum temperatures: 23–25°C.
- Maximum temperatures: 31–34°C.
- Northeasterly winds at 10–30 km/h.
