UPDATE: Phuket faces isolated heavy rain as TMD warning runs through September 13

The Thai Meteorological Department (TMD) forecasts thunderstorms across 70% of Thailand’s west coast, including Phuket, on 11–12 September 2026, with isolated heavy rain in the province.

The TMD’s 12 September 2026 outlook, covering the 24 hours from 6am on 12 September to 6am on 13 September, puts thunderstorms over 70% of the south-west coast. It forecasts isolated heavy rain in Phuket, Krabi, Trang and Satun, and isolated very heavy rain in Ranong and Phang Nga.

A Nation Thailand report published on 11 September said the TMD had issued its 10th warning for heavy to very heavy rain through 13 September, covering 24 provinces. The provinces specifically named in the report included Phuket, Krabi, Chumphon, Surat Thani, Nakhon Si Thammarat, Phatthalung, Songkhla, Pattani, Yala, Narathiwat, Ranong, Phang Nga, Trang and Satun.

Temperatures along the west coast are forecast to range from 23–32°C. The TMD warns that heavy and accumulated rain may trigger flash floods, forest runoff and landslides in vulnerable areas, particularly near foothills, waterways and low-lying ground. It also advises people to avoid routes that regularly flood, especially low-lying roads where temporary inundation could develop.

Marine conditions are expected to be moderate. From Phuket northwards, westerly winds are forecast at 20–35 kilometres per hour, with waves around 2 metres and above 2 metres during thunderstorms. From Krabi southwards, north-westerly winds of 15–35 kilometres per hour are expected, with waves of 1–2 metres and above 2 metres during thunderstorms. The TMD advises boat operators in the Andaman Sea to navigate cautiously and avoid thunderstorms.

The TMD said rainfall is expected to increase across the South between 11 and 13 September, with heavy to very heavy rain in some areas. It said the pattern is being influenced by a high-pressure system or cool air mass from southern China pushing the monsoon trough southwards, while the south-westerly monsoon over the Andaman Sea, the South and the Gulf of Thailand is expected to strengthen.

The department also said a strong low-pressure area over the central South China Sea could strengthen into a tropical cyclone and move closer to the coast of upper Vietnam on 13–14 September. Residents are advised to follow official forecasts and warnings when planning travel and daily activities. Updates are available from the TMD website and its 24-hour telephone services at 0-2399-4012-13 and 1182.