Bangkok: The Meteorological Department has issued a warning of heavy to very heavy rainfall across Thailand from June 28 to July 4, with potential risks of flash floods and river overflows.

According to Thai News Agency, the Meteorological Department predicts increased rainfall due to a strengthening southwest monsoon over the Andaman Sea, Thailand, and the Gulf of Thailand, alongside a monsoon trough moving southward through Myanmar, Laos, and Vietnam. The forecast for June 28, 2026, indicates heavy rain in some areas, particularly in the eastern and western southern regions. Thunderstorms, heavy rain, and accumulated rainfall pose significant dangers, with wave conditions in the upper Andaman Sea expected to be moderate, reaching heights of approximately 2 meters, and exceeding 2 meters during thunderstorms.

The 7-day weather forecast anticipates intensified rainfall, especially from June 29th to July 3rd, 2026, due to the monsoon trough over northern and northeastern Thailand. The Andaman Sea and the Gulf of Thailand are expected to experience stronger wave conditions. Mariners are advised to remain cautious, with waves reaching 2-3 meters in the upper Andaman Sea and exceeding 3 meters during thunderstorms. Similar conditions are expected in the lower Andaman Sea and upper Gulf of Thailand.

The Meteorological Department cautions the public to remain vigilant about the risks of flash floods, landslides, and river overflows, particularly in hillside and low-lying areas. Mariners are advised to avoid sailing in thunderstorm-prone areas, and small boats in the upper Andaman Sea should stay ashore from June 29th to July 4th, 2026.

Additionally, the department reported an earthquake of magnitude 3.8 north of the Sumatra Islands, Indonesia, and smaller quakes in Myanmar, none of which impacted Thailand.