Bangkok: Southern Thailand is warned to prepare for increased rainfall on May 28-29 as a strengthening monsoon covers the Andaman Sea and the Gulf of Thailand. Three provinces will experience the full impact of 70% of the rain.
According to Thai News Agency, the Meteorological Department forecasts that over the next 24 hours, Thailand will experience thunderstorms and heavy rainfall in some areas, particularly in the western part of the southern region. This is due to a moderate southwest monsoon covering the Andaman Sea, Thailand, and the Gulf of Thailand. The public is advised to be aware of the dangers from heavy rainfall and accumulated rainwater during this period.
Wave conditions in the Andaman Sea and the Gulf of Thailand are moderate. In the upper Andaman Sea, waves are approximately 2 meters high, while in the lower Andaman Sea and upper Gulf of Thailand, waves are 1-2 meters high. In areas with thunderstorms, waves may exceed 2 meters. Mariners in these areas are advised to exercise caution and avoid sailing in areas with thunderstorms.
Furthermore, during May 28-29, 2026, the southern region will experience increased rainfall and heavy to very heavy rain in some areas, mostly along the western coast, due to the strengthening of the southwest monsoon covering the Andaman Sea, Thailand, and the Gulf of Thailand. Wave conditions in the Andaman Sea will also intensify, with waves reaching 2-3 meters in the upper Andaman Sea, and exceeding 3 meters in areas with thunderstorms.
The weather forecast for Thailand includes a 40% chance of thunderstorms in the North, Northeast, Central, and Eastern regions, with varying temperatures and wind speeds. The southern region (eastern coast) shows a 40% chance of thunderstorms, while the western coast expects a 70% chance of thunderstorms and heavy rain in provinces like Ranong, Phang Nga, and Phuket. Bangkok and surrounding areas also anticipate a 40% chance of thunderstorms, mostly in the afternoon and evening.