Monsoon covers Thailand as heavy rain affects 60-70% of areas
The department warns people in risk areas to prepare for heavy rainfall, standing water, flash floods, and runoff, while small boats should stay ashore.
- A strong south-westerly monsoon is causing heavy rainfall across 60-70% of Thailand, particularly in the North, Central, East, and South regions.
- The public is warned to prepare for potential flash floods and run-off, especially in low-lying areas and near waterways.
- Mariners are advised of rough seas with waves reaching 2-3 meters, and small boats in the Andaman Sea and upper Gulf of Thailand are urged to remain ashore.
The Thai Meteorological Department (TMD) forecast on Friday (June 5, 2026) that upper Thailand would see more rain over the next 24 hours, with heavy rain in some areas.
Very heavy rain is expected in parts of the North, the western side of the Central region, the East, and the west coast of the South, as a fairly strong south-westerly monsoon prevails over the Andaman Sea, Thailand, and the Gulf of Thailand.
People in these areas are advised to prepare for heavy to very heavy rainfall and accumulated rain, which could cause flash floods and run-off, particularly in risk areas near waterways and low-lying zones.
Seas in the upper Andaman Sea and the upper Gulf of Thailand are expected to be fairly rough, with waves 2-3 metres high and above 3 metres in thundershowers.
Mariners in the Andaman Sea and Gulf of Thailand are advised to navigate with caution and avoid areas with thundershowers.
Small boats in the Andaman Sea and the upper Gulf of Thailand should remain ashore during this period.
Weather forecast for Thailand from 6am on Friday (June 5, 2026) to 6am on Saturday (June 6, 2026)
The North
- Thundershowers are expected in 60% of the area, with heavy rain in some places.
- Affected provinces include Mae Hong Son, Chiang Mai, Tak, Phayao, Phrae, Nan, Kamphaeng Phet, Phitsanulok, and Phetchabun.
- Minimum temperature: 23-26 degrees Celsius
- Maximum temperature: 35-38 degrees Celsius
- South-westerly winds: 10-20 km/h
The Northeast
- Thundershowers are expected in 60% of the area, with heavy rain in some places.
- Affected provinces include Loei, Nong Khai, Bueng Kan, Sakon Nakhon, Nakhon Phanom, Chaiyaphum, and Nakhon Ratchasima.
- Minimum temperature: 23-26 degrees Celsius
- Maximum temperature: 34-36 degrees Celsius
- South-westerly winds: 10-20 km/h
The Central region
- Thundershowers are expected in 60% of the area, with heavy to very heavy rain in some places.
- Affected provinces include Nakhon Sawan, Uthai Thani, Kanchanaburi, Ratchaburi, Suphan Buri, Nakhon Pathom, Samut Songkhram, Samut Sakhon, and Phra Nakhon Si Ayutthaya.
- Minimum temperature: 25-27 degrees Celsius
- Maximum temperature: 34-36 degrees Celsius
- South-westerly winds: 10-20 km/h
The East
- Thundershowers are expected in 70% of the area, with heavy to very heavy rain in some places.
- Affected provinces include Nakhon Nayok, Prachin Buri, Chachoengsao, Sa Kaeo, Chonburi, Rayong, Chanthaburi, and Trat.
- Minimum temperature: 24-28 degrees Celsius
- Maximum temperature: 32-35 degrees Celsius
- South-westerly winds: 20-40 km/h
- Seas will have waves 2-3 metres high, rising above 3 metres in thundershowers.
The South (East Coast)
- Thundershowers are expected in 60% of the area, with heavy rain in some places.
- Affected provinces include Phetchaburi, Prachuap Khiri Khan, Chumphon, Surat Thani, and Nakhon Si Thammarat.
- Minimum temperature: 24-27 degrees Celsius
- Maximum temperature: 32-35 degrees Celsius
- From Surat Thani northwards: south-westerly winds at 20-40 km/h
- Seas will have waves 1-2 metres high, rising above 2 metres offshore and in thundershowers.
- From Nakhon Si Thammarat southwards: south-westerly winds at 20-35 km/h
- Seas will have waves 1-2 metres high, around 2 metres offshore and above 2 metres in thundershowers.
The South (west coast)
- Thundershowers are expected in 70% of the area, with heavy to very heavy rain in some places.
- Affected provinces include Ranong, Phang Nga, Phuket, Krabi, Trang, and Satun.
- Minimum temperature: 24-25 degrees Celsius
- Maximum temperature: 29-32 degrees Celsius
- From Phang Nga northwards: south-westerly winds at 20-40 km/h
- Seas will have waves 2-3 metres high, rising above 3 metres in thundershowers.
- From Phuket southwards: south-westerly winds at 20-35 km/h
- Seas will have waves around 2 metres high, rising above 2 metres in thundershowers.
Bangkok and the surrounding provinces
- Thundershowers are expected in 60% of the area, with heavy rain in some places.
- Minimum temperature: 25-28 degrees Celsius
- Maximum temperature: 33-34 degrees Celsius
- South-westerly winds: 10-20 km/h
