Monsoon brings heavy rain and flood risks across Thailand

Thailand is facing widespread rain and possible flash floods as a relatively strong southwest monsoon continues to cover the Andaman Sea, the country and the Gulf of Thailand, while a low-pressure cell remains over upper Myanmar.

The Thai Meteorological Department’s 24-hour forecast, issued for the period from 6am on June 6 to 6am the following day, warned of heavy rain in parts of the upper Northeast, the East, the western coast of the South and the Central region. Very heavy rain was also expected in some western areas of the North.

Authorities urged people in affected areas to prepare for heavy to very heavy rain and accumulated rainfall, which could trigger flash floods and forest run-off, particularly in low-lying areas and communities near waterways.

Marine conditions are also expected to remain hazardous. Waves in the upper Andaman Sea are forecast at 2-3 metres, rising above 3 metres during thunderstorms. Boat operators in the Andaman Sea and the Gulf of Thailand have been advised to navigate with caution and avoid sailing in stormy areas. Small boats in the upper Andaman Sea should remain ashore for the time being.

Regional forecast

North

• Thunderstorms in 70% of the region
• Heavy rain in Chiang Mai, Chiang Rai, Lamphun, Lampang, Phayao, Nan and Phrae
• Very heavy rain in Mae Hong Son and Tak
• Minimum temperature: 23-25C
• Maximum temperature: 31-34C

Northeast

• Thunderstorms in 60% of the region
• Heavy rain in Nong Khai, Bueng Kan, Udon Thani, Sakon Nakhon and Nakhon Phanom
• Minimum temperature: 23-26C
• Maximum temperature: 31-35C

Central region

• Thunderstorms in 40% of the region
• Heavy rain in Uthai Thani, Kanchanaburi and Ratchaburi
• Minimum temperature: 25-27C
• Maximum temperature: 32-35C

East

• Thunderstorms in 40% of the region
• Heavy rain in Nakhon Nayok, Prachin Buri, Rayong, Chanthaburi and Trat
• Minimum temperature: 24-28C
• Maximum temperature: 30-35C
• Seas about 2 metres high, rising above 2 metres during thunderstorms

South, east coast

• Thunderstorms in 60% of the region, mostly in Phetchaburi, Prachuap Khiri Khan, Chumphon, Surat Thani and Nakhon Si Thammarat
• Minimum temperature: 24-25C
• Maximum temperature: 33-36C
• Waves 1-2 metres high, about 2 metres offshore and above 2 metres during thunderstorms

South, west coast

• Thunderstorms in 70% of the region
• Heavy rain in Ranong, Phang Nga and Phuket
• Minimum temperature: 24-25C
• Maximum temperature: 29-35C
• From Phang Nga northwards, waves are expected at 2-3 metres and above 3 metres during thunderstorms
• From Phuket southwards, waves are expected at about 2 metres and above 2 metres during thunderstorms

Bangkok and surrounding provinces

• Thunderstorms in 40% of the area
• Minimum temperature: 26-28C
• Maximum temperature: 33-35C