TMD warns 56 provinces of heavy rain and flood risk

The Thai Meteorological Department (TMD) has warned of heavy to very heavy rain across 56 provinces on Saturday, May 30, with people in risk areas urged to prepare for possible flash floods and forest run-off.

The latest 24-hour forecast, issued from 6am on Saturday to 6am on Sunday, says Thailand will see continuous rainfall, with heavy rain in several areas and very heavy rain expected in parts of the North, Central region and the western coast of the South.

The conditions are being driven by a rather strong south-west monsoon prevailing over the Andaman Sea, Thailand and the Gulf of Thailand. A monsoon trough is also lying across the North, upper Central region and lower Northeast, extending into a low-pressure cell over the coast of central Vietnam.

The department advised people across the country to remain alert to danger from heavy to very heavy rain and accumulated rainfall, particularly in low-lying areas and communities near waterways.

Rain forecast by region

North

Thunderstorms are forecast in 70% of the region.

• Heavy to very heavy rain is expected in some areas.
• Provinces at risk include Mae Hong Son, Chiang Mai, Lamphun, Lampang, Uttaradit, Tak, Sukhothai, Kamphaeng Phet, Phichit, Phitsanulok and Phetchabun.
• Temperatures: lows of 22-25 degrees Celsius and highs of 34-36C.
• South-westerly winds: 10-25 kilometres per hour.

Northeast

• Thunderstorms are forecast in 60% of the region.
• Heavy rain is expected in some areas.
• Provinces at risk include Loei, Nong Khai, Bueng Kan, Nong Bua Lamphu, Udon Thani, Chaiyaphum, Khon Kaen, Amnat Charoen, Nakhon Ratchasima, Buri Ram, Surin, Si Sa Ket and Ubon Ratchathani.
• Temperatures: lows of 23-25C and highs of 34-36C.
• South-westerly winds: 10-20kph.

Central region

• Thunderstorms are forecast in 60% of the region.
• Heavy to very heavy rain is expected in some areas.
• Provinces at risk include Nakhon Sawan, Uthai Thani, Saraburi, Phra Nakhon Si Ayutthaya, Suphan Buri, Kanchanaburi, Ratchaburi and Samut Sakhon.
• Temperatures: lows of 24-26C and highs of 35-37C.
• South-westerly winds: 10-25kph.

East

• Thunderstorms are forecast in 60% of the region.
• Heavy rain is expected in some areas.
• Provinces at risk include Nakhon Nayok, Prachin Buri, Sa Kaeo, Chachoengsao, Chonburi, Rayong, Chanthaburi and Trat.
• Temperatures: lows of 25-28C and highs of 33-37C.
• South-westerly winds: 15-35kph.
• Waves are expected to reach 1-2 metres, rising above 2 metres during thunderstorms.

South, east coast

• Thunderstorms are forecast in 60% of the region.
• Heavy rain is expected in some areas.
• Provinces at risk include Phetchaburi, Prachuap Khiri Khan, Chumphon, Surat Thani and Nakhon Si Thammarat.
• Temperatures: lows of 24-26C and highs of 33-36C.
• South-westerly winds: 15-35kph.
• Waves are expected to reach around 1 metre, rising to 1-2 metres offshore and above 2 metres during thunderstorms.

South, west coast

• Thunderstorms are forecast in 70% of the region.
• Heavy to very heavy rain is expected in some areas.
• Provinces at risk include Ranong, Phang Nga, Phuket, Krabi and Trang.
• Temperatures: lows of 23-26C and highs of 31-34C.
• From Phuket northwards, south-westerly winds are forecast at 20-40kph, with waves of 2-3 metres and above 3 metres during thunderstorms.
• From Krabi southwards, south-westerly winds are forecast at 20-35kph, with waves of around 2 metres and above 2 metres during thunderstorms.

Bangkok and surrounding provinces

• Thunderstorms are forecast in 60% of the area.
• Heavy rain is expected in some places.
• Temperatures: lows of 25-27C and highs of 34-37C.
• South-westerly winds: 10-25kph.

Marine warning

The upper Andaman Sea, from Phuket northwards, will see rather strong winds and waves of 2-3 metres. Waves could rise above 3 metres in thunderstorm areas.

The lower Andaman Sea, from Krabi southwards, is expected to see waves of around 2 metres, while the upper Gulf of Thailand will see waves of 1-2 metres. In thunderstorm areas, waves may exceed 2 metres.

Boat operators are advised to proceed with caution and avoid sailing in thunderstorm areas. Small boats in the upper Andaman Sea should remain ashore during this period.

Public advice

People are advised to:

• follow TMD announcements closely;
• plan travel carefully and avoid flood-prone routes where possible;
• watch for flash floods and forest run-off, especially in low-lying areas and near waterways;
• avoid marine travel in areas with thunderstorms;
• keep small boats ashore in the upper Andaman Sea.