Heavy rain to lash Thailand under four-day monsoon warning

The Thai Meteorological Department (TMD) issued Announcement No 9 at 5pm on Monday (July 27), warning of heavy to very heavy rain across Thailand until July 30.

From July 27–30, heavy rain is forecast across many areas, with very heavy rain expected in some locations in the North, Northeast, Central region and East, as well as along the South’s west coast.

The conditions are being driven by a monsoon trough extending across the North and upper Northeast, together with a relatively strong southwest monsoon prevailing over the Andaman Sea, Thailand and the Gulf of Thailand.

The public has been urged to remain alert to heavy rain and accumulated rainfall, which could trigger flash floods and run-off, particularly in foothill areas near waterways and in low-lying areas.

Seas in the upper Andaman Sea are also expected to remain relatively rough, with waves of 2–3 metres, rising above three metres in thundery areas.

Waves in the upper Gulf of Thailand and lower Andaman Sea are forecast to reach about two metres, rising above two metres in thundery areas.

Mariners in the Andaman Sea and Gulf of Thailand should proceed with caution and avoid sailing in areas affected by thunderstorms. Small boats in the upper Andaman Sea should remain ashore throughout the period.

The provinces expected to be affected by heavy to very heavy rain from July 27–30 are listed below.

July 27

Very heavy rain

• East: Trat.

Heavy rain

• North: Mae Hong Son, Chiang Rai, Nan, Tak, Phitsanulok and Phetchabun.
• Northeast: Nong Khai, Bueng Kan, Udon Thani, Sakon Nakhon, Nakhon Phanom, Mukdahan, Yasothon, Amnat Charoen, Ubon Ratchathani and Si Sa Ket.
• Central region: Kanchanaburi and Ratchaburi.
• East: Chanthaburi.
• South: Ranong and Phang Nga.

July 28

Very heavy rain

• Northeast: Nong Khai, Bueng Kan, Nakhon Phanom, Mukdahan, Amnat Charoen and Ubon Ratchathani.
• East: Rayong, Chanthaburi and Trat.
• South: Ranong and Phang Nga.

Heavy rain

• North: Mae Hong Son, Chiang Mai, Chiang Rai, Phayao, Nan, Tak, Phitsanulok and Phetchabun.
• Northeast: Udon Thani, Sakon Nakhon, Kalasin, Roi Et, Yasothon and Si Sa Ket.
• Central region: Kanchanaburi, Ratchaburi and Saraburi.
• East: Nakhon Nayok, Prachin Buri and Rayong.
• South: Chumphon, Surat Thani, Nakhon Si Thammarat, Phatthalung, Phuket, Krabi and Trang.

July 29

Very heavy rain

• Northeast: Nong Khai, Bueng Kan, Kalasin, Maha Sarakham, Roi Et, Mukdahan, Yasothon, Amnat Charoen and Ubon Ratchathani.
• Central region: Kanchanaburi.
• East: Sa Kaeo, Chachoengsao, Rayong, Chanthaburi and Trat.
• South: Ranong, Phang Nga and Phuket.

Heavy rain

• North: Mae Hong Son, Chiang Mai, Chiang Rai, Phayao, Nan, Uttaradit, Tak, Kamphaeng Phet, Phitsanulok, Phichit and Phetchabun.
• Northeast: Loei, Udon Thani, Sakon Nakhon, Nakhon Phanom, Chaiyaphum, Nakhon Ratchasima, Buri Ram, Surin and Si Sa Ket.
• Central region: Nakhon Sawan, Uthai Thani, Lop Buri, Saraburi and Ayutthaya, as well as Bangkok and surrounding provinces.
• East: Nakhon Nayok, Prachin Buri and Chon Buri.
• South: Prachuap Khiri Khan, Chumphon, Surat Thani, Nakhon Si Thammarat, Phatthalung, Krabi and Trang.

July 30

Very heavy rain

• North: Phetchabun.
• East: Nakhon Nayok, Rayong, Chanthaburi and Trat.
• South: Ranong.

Heavy rain

• North: Mae Hong Son, Chiang Mai, Nan, Uttaradit, Tak, Kamphaeng Phet, Sukhothai and Phichit.
• Northeast: Loei, Nong Khai, Bueng Kan, Nong Bua Lamphu, Udon Thani, Chaiyaphum, Khon Kaen, Nakhon Ratchasima, Buri Ram and Surin.
• Central region: Nakhon Sawan, Uthai Thani, Saraburi, Ayutthaya, Kanchanaburi, Ratchaburi, Nakhon Pathom and Samut Sakhon, as well as Bangkok and surrounding provinces.
• East: Prachin Buri, Sa Kaeo, Chachoengsao and Chon Buri.
• South: Phetchaburi, Prachuap Khiri Khan, Chumphon, Surat Thani, Phang Nga, Phuket and Krabi.

To improve safety and minimise possible disruption, residents are advised to plan their daily activities and journeys carefully during the affected period.

The public should continue monitoring TMD announcements via the department’s website or telephone lines 0-2399-4012-13 and 1182, which are available around the clock.

The department is due to issue its next announcement at 5am on Tuesday (July 28).