Bangkok: The Meteorological Department of Thailand has issued a warning about the likelihood of more frequent storms towards the end of September, particularly impacting the Pacific Ocean and the South China Sea. These weather patterns, though not directly affecting Thailand, are expected to influence the country's climate, resulting in increased rainfall and potentially heavy rain in several regions.
According to Thai News Agency, Mr. Somkuan Tonjan, Director of the Weather Forecast Division, highlighted the increased frequency of storms in the Pacific Ocean and South China Sea, especially between September 26th and 27th. Although the precise trajectory of these storms remains uncertain, the department emphasizes the need for careful monitoring of their development.
Typhoon Rakasa, currently active over the western Pacific Ocean, is not anticipated to directly impact Thailand. However, it is affecting the country's weather by altering the monsoon trough and southwest monsoon. This alteration is leading to heightened rainfall across various regions, with some areas experiencing heavy to very heavy rainfall from September 21-27, 2025.
The regions identified for close observation due to the potential for heavy rainfall and accumulation include Bangkok and its vicinity, the Eastern region such as Chanthaburi and Trat, and certain parts of the lower Northern and Northeastern regions, including Mae Hong Son, Tak, Ubon Ratchathani, and Amnat Charoen. These areas are at risk of flash floods, forest runoff, and flooding, particularly in hillside regions and near waterways.
Concerning maritime conditions, between September 21-23, the upper Andaman Sea is expected to experience waves around 2 meters high, while the lower Andaman Sea and upper Gulf of Thailand may see waves ranging from 1-2 meters. Thunderstorm activity could elevate wave heights to over 2 meters.
From September 24-27, the wave intensity in the upper Andaman Sea is projected to increase, with waves reaching 2-3 meters high. Thunderstorm-prone areas may see waves exceeding 3 meters. The lower Andaman Sea and upper Gulf of Thailand will likely encounter waves around 2 meters high. The Meteorological Department advises small boats in the upper Andaman Sea to remain ashore from September 24-26 and urges sailors to exercise caution, avoiding areas with thunderstorms during this period.
Looking ahead to early October (2-5 October), rainfall is expected to decrease slightly, though weather conditions remain unstable, necessitating continuous monitoring.
The Meteorological Department encourages the public to adhere to official warnings and weather forecasts, while avoiding unverified information or analyses without credible sources.