Six southern provinces warned of flash floods and forest run-off from June 3-8

The Department of Disaster Prevention and Mitigation (DDPM) on Wednesday issued a warning for six southern provinces to monitor possible flash floods and forest run-off from June 3-8, 2026.

The DDPM cited the Southern Meteorological Centre for the west coast, which reported that from June 2-4, a rather strong south-westerly monsoon would prevail over the Andaman Sea and the western coast of southern Thailand.

This will bring more rain to the South’s west coast, with heavy to very heavy rain in some areas, which could trigger flash floods and forest run-off.

Waves in the Andaman Sea are also expected to strengthen. In the upper Andaman Sea, waves are forecast to reach 2-3 metres, and more than 3 metres in thunderstorm areas. In the lower Andaman Sea, waves are expected to be about 3 metres, and more than 2 metres in thunderstorm areas.

The weather outlook for June 2-8 indicates that the western coast of the South will continue to see heavy rain. Areas at risk of heavy rainfall, forest run-off, flash floods, waterlogging, mudslides and strong waves from June 3-8 are as follows.

Six provinces under watch for forest run-off, flash floods, waterlogging and mudslides:

• Ranong
• Phang Nga
• Phuket
• Krabi
• Trang
• Satun

Four provinces under watch for strong waves:

• Ranong: Mueang, Suk Samran and Kapoe districts
• Phang Nga: Ko Yao, Takua Thung, Thai Mueang, Takua Pa and Khura Buri districts
• Phuket: all districts
• Krabi: Mueang, Khlong Thom, Ko Lanta, Nuea Khlong and Ao Luek districts

The DDPM has coordinated with the six southern provinces and regional disaster prevention and mitigation centres to closely monitor the situation and prepare response measures.

Officials have been instructed to continuously monitor weather and water conditions, while operational teams and disaster-response machinery must be stationed in risk areas to provide timely assistance to the public.

For natural tourist attractions, especially waterfalls, caves and through-caves, authorities should issue warnings and block access if there is a risk of danger.

In the event of strong waves, relevant agencies should issue announcements or install warning signs along the coast to prohibit tourists from swimming. Boat operators, captains and passenger boat service providers should exercise greater caution when sailing.

If conditions appear likely to worsen, authorities should consider imposing a strict ban on boat operations.

Officials must also remain on alert in risk areas and be ready to assist the public 24 hours a day. Temporary shelters should be prepared in case evacuations are needed, with sufficient food, drinking water and essential supplies.

Members of the public are advised to strictly follow official warnings and instructions.

People can follow disaster alerts via the THA Disaster Alert application and request assistance through the 1784 hotline, available 24 hours a day.