Monsoon trough triggers heavy rain in 46 provinces, 70% of Thailand affected
Meteorological Department warns of monsoon trough causing 70% rainfall, flash floods and storms in 46 provinces with strong winds and rough seas
The Meteorological Department has issued a weather warning as the monsoon trough sweeps across Thailand, bringing heavy to very heavy rain to 70% of the country. People are urged to watch for flash floods and forest run-off, especially in foothill areas, near waterways, and low-lying zones.
A total of 46 provinces are under alert for thunderstorms, strong winds, and rough seas. In the North and East, very heavy rainfall is expected, particularly in Chiang Rai, Phayao, Nan, Phrae, Loei, Bueng Kan, Chanthaburi, and Trat.
The monsoon trough lies across upper Myanmar, northern and northeastern Thailand, and upper Vietnam, while a low-pressure system over southern China is moving along the same axis. Meanwhile, the strengthening southwesterly monsoon continues to affect the Andaman Sea, Thailand, and the Gulf of Thailand.
Marine conditions
Waves in the upper Andaman Sea are expected to reach 2 metres, and 1–2 metres elsewhere in the Andaman and upper Gulf of Thailand. Thunderstorms may bring waves exceeding 2 metres.
Fisherfolk and boat operators are advised to proceed with caution and avoid sailing in storm-affected areas.
Thailand Weather Forecast
From 6am Friday (July 11) to 6am Saturday (July 12)
North
• Thunderstorms in 70% of the area; heavy to very heavy rain in some parts
• Affected provinces: Mae Hong Son, Chiang Mai, Chiang Rai, Phayao, Nan, Phrae, Tak, Sukhothai, Uttaradit, Phitsanulok, Phetchabun
• Low: 23–26°C | High: 29–34°C
• Southwesterly winds 10–20 km/h
Northeast
• Thunderstorms in 70% of the area; heavy rain in some parts
• Affected provinces: Loei, Nong Khai, Bueng Kan, Udon Thani, Nong Bua Lam Phu, Sakon Nakhon, Nakhon Phanom, Mukdahan, Amnat Charoen, Ubon Ratchathani
• Low: 22–26°C | High: 29–33°C
• Southwesterly winds 10–20 km/h
Central
• Thunderstorms in 60% of the area; heavy rain in some parts
• Affected provinces: Nakhon Sawan, Uthai Thani, Kanchanaburi, Ratchaburi
• Low: 24–26°C | High: 32–34°C
• Southwesterly winds 10–20 km/h
East
• Thunderstorms in 70% of the area; heavy to very heavy rain in some parts
• Affected provinces: Nakhon Nayok, Prachin Buri, Sa Kaeo, Chachoengsao, Chonburi, Rayong, Chanthaburi, Trat
• Low: 24–28°C | High: 30–34°C
• Southwesterly winds 15–35 km/h
• Waves 1–2 metres, over 2 metres in stormy areas
South (East Coast)
• Thunderstorms in 40% of the area; heavy rain in some parts
• Affected provinces: Chumphon, Surat Thani, Nakhon Si Thammarat
• Low: 24–26°C | High: 32–35°C
• Southwesterly winds 15–35 km/h
• Waves ~1 metre, offshore 1–2 metres; over 2 metres in thunderstorms
South (West Coast)
• Thunderstorms in 60% of the area; heavy rain in some parts
• Affected provinces: Ranong, Phang Nga, Phuket, Krabi
• From Krabi northwards:
– Southwesterly winds 20–35 km/h
– Waves ~2 metres, over 2 metres in stormy areas
• From Trang southwards:
– Southwesterly winds 15–35 km/h
– Waves 1–2 metres, over 2 metres in thunderstorms
Bangkok and Surrounding Areas
• Thunderstorms in 60% of the area
• Low: 26–27°C | High: 32–35°C
• Southwesterly winds 10–20 km/h
