Heavy rain forecast for Phuket as monsoon strengthens

Thailand’s Meteorological Department has warned that parts of Phuket could face heavy rain through Sunday, 9 August, as a strong south-westerly monsoon affects Thailand.

The department said heavy to very heavy rain and accumulated rainfall could trigger flash floods and run-off, particularly near foothills, waterways and low-lying areas. Ranong and Phang Nga are also among the southern provinces listed for heavy rain.

The upper Andaman Sea is expected to have waves 2–4 metres high, rising above 4 metres during thunderstorms. Mariners have been advised to exercise caution and avoid thunderstorms, while small boats in the upper Andaman Sea should remain ashore from 6–9 August.

The weather warning, issued at 5pm on Thursday, 6 August 2026, covers heavy rain, strong winds and high waves across parts of Thailand. The department attributed the conditions to a monsoon trough over the upper North and upper Northeast combined with the strong south-westerly monsoon.

The department said Typhoon Dolphin was a separate system and was forecast to pass over Okinawa, Japan, from 6–7 August before making landfall in China’s Zhejiang province from 9–10 August. It was not expected to move into Thailand.