Monsoon trough brings heavy rain and 60% storms to Bangkok

Thailand will continue to see isolated heavy rain over the next 24 hours, with very heavy falls forecast in parts of the East as a monsoon trough crosses Myanmar and the upper North towards a low-pressure area over upper Vietnam.

A relatively strong southwest monsoon is also prevailing over the Andaman Sea, Thailand and the Gulf of Thailand, contributing to unsettled weather across much of the country.

People in affected areas have been warned to watch for hazards from heavy and accumulated rainfall, including flash floods and forest run-off, particularly near foothills, waterways and low-lying areas. Residents in the Northeast should also remain alert for overflowing waterways.

Upper Andaman waves reach 2-3 metres

Conditions in the upper Andaman Sea will remain relatively rough, with waves of 2-3 metres and more than three metres in thunderstorms.

Mariners are advised to navigate with caution and avoid areas affected by thunderstorms, while small boats in the upper Andaman Sea should remain ashore.  

Regional forecast from 6am Saturday to 6am Sunday

Bangkok and surrounding provinces

• Thunderstorms across 60% of the area, with isolated heavy rain
• Minimum temperature: 26-27C
• Maximum temperature: 33-35C
• Southwesterly winds: 10-25 km/h

North

• Thunderstorms across 60% of the region
• Isolated heavy rain in Mae Hong Son, Chiang Mai, Chiang Rai, Phayao, Nan and Tak
• Minimum temperature: 23-28C
• Maximum temperature: 32-35C
• Southwesterly winds: 10-20 km/h

Northeast

• Thunderstorms across 60% of the region
• Isolated heavy rain in Udon Thani, Nong Khai, Bueng Kan, Sakon Nakhon, Nakhon Phanom, Mukdahan, Amnat Charoen and Ubon Ratchathani
• Minimum temperature: 24-26C
• Maximum temperature: 33-35C
• Southwesterly winds: 10-20 km/h

Central region

• Thunderstorms across 40% of the region
• Isolated heavy rain in Saraburi and Kanchanaburi
• Minimum temperature: 25-27C
• Maximum temperature: 34-36C
• Southwesterly winds: 10-25 km/h

East

• Thunderstorms across 60% of the region
• Isolated heavy rain in Nakhon Nayok and Prachin Buri
• Isolated very heavy rain in Chanthaburi and Trat
• Minimum temperature: 25-28C
• Maximum temperature: 31-34C
• Southwesterly winds: 20-35 km/h
• Waves around two metres, rising above two metres in thunderstorms

South — east coast

• Thunderstorms across 40% of the region, mainly in Chumphon, Surat Thani, Nakhon Si Thammarat, Songkhla, Yala and Narathiwat
• Minimum temperature: 23-26C
• Maximum temperature: 33-35C
• Southwesterly winds: 20-35 km/h
• Waves of 1-2 metres, around two metres offshore and above two metres in thunderstorms

South — west coast

• Thunderstorms across 60% of the region
• Isolated heavy rain in Trang and Satun
• Minimum temperature: 24-28C
• Maximum temperature: 32-34C
• From Phang Nga northwards: southwesterly winds of 20-40 km/h, with waves of 2-3 metres and above three metres in thunderstorms
• From Phuket southwards: southwesterly winds of 15-35 km/h, with waves of 1-2 metres and above two metres in thunderstorms