The Thai Meteorological Department has issued a new warning for heavy to very heavy rain, storms, strong winds and hail from 9 to 13 October 2026, particularly affecting the South.
The Thai Meteorological Department has issued its second alert bulletin regarding abundant to very abundant rainfall across a large part of the country. The period of unsettled weather is expected from 9 to 13 October 2026, with thunderstorms, strong winds and hail in several regions.
This situation results from the combination of a mass of cool air from China extending over northern Thailand at the end of the rainy season, a monsoon trough positioned over the upper South, and the continued south-west monsoon over the Andaman Sea, the South and the Gulf of Thailand.
In the South, several provinces are particularly affected. Surat Thani (home to Koh Samui) is among the areas likely to receive sustained rain on 9, 10 and 12 October. Phuket is also mentioned for significant rainfall on 10 and 12 October, alongside Phang Nga, Krabi, Ranong and Trang.
Koh Samui forecast:
| Date | Conditions | Temperatures | Rain |
|---|---|---|---|
| 8 October | Cloudy with showers and thunderstorms ⛈️ | 🌡 30°C / 26°C | 🌧 High (70%) |
| 9 October | Thunderstorms and sustained rain ⛈️ | 🌡 31°C / 26°C | 🌧 High (80%) |
| 10 October | Heavy rain and thunderstorms ⛈️ | 🌡 30°C / 26°C | 🌧 Very high (85%) |
| 11 October | Thundery showers 🌧 | 🌡 30°C / 26°C | 🌧 High (70%) |
| 12 October | Rain and thunderstorms ⛈️ | 🌡 30°C / 26°C | 🌧 High (75%) |
| 13 October | Scattered showers 🌧 | 🌡 29°C / 26°C | 🌧 Possible (50%) |
Phuket forecast:
| Date | Conditions | Temperatures | Rain |
|---|---|---|---|
| 8 October | Cloudy with showers 🌧 | 🌡 30°C / 26°C | 🌧 High (65%) |
| 9 October | Showers and thunderstorms ⛈️ | 🌡 30°C / 26°C | 🌧 High (75%) |
| 10 October | Thunderstorms and sustained rain ⛈️ | 🌡 30°C / 26°C | 🌧 Very high (80%) |
| 11 October | Thundery showers ⛈️ | 🌡 29°C / 26°C | 🌧 High (70%) |
| 12 October | Rain and thunderstorms ⛈️ | 🌡 30°C / 26°C | 🌧 High (75%) |
| 13 October | Showers 🌧 | 🌡 29°C / 26°C | 🌧 Possible (55%) |
Authorities are urging the public to remain extremely vigilant in the face of risks of sudden flooding and run-off, particularly near waterways and in low-lying areas. Residents in low-lying zones are advised to prepare for possible flooding.
"The department has urged residents to beware of thunderstorms, strong winds, heavy to very heavy rain and accumulated rainfall, which could cause flash floods and run-off, especially in foothill areas, near waterways and in low-lying zones."
At sea, waves on the Andaman Sea and the Gulf of Thailand could exceed two metres in areas affected by storms. Mariners are advised to check weather conditions carefully and to avoid putting to sea.
Source: TMD weather forecasts