Upper Thailand is on alert for significant rainfall, with the Thai Meteorological Department (TMD) issuing a warning for heavy to very heavy downpours expected from August 29 through September 2. This forecast indicates a substantial shift in weather patterns, prompting advisories for residents in affected areas.
Understanding the Weather System
The current weather situation is attributed to a combination of meteorological factors. A monsoon trough is migrating southward, directly impacting the northern and eastern regions of Thailand. Compounding this, a low-pressure system situated over northern Vietnam is contributing to the developing weather. Furthermore, a robust southwest monsoon is active across the Andaman Sea, the entirety of Thailand, and the Gulf of Thailand, intensifying the rainfall potential.
Regional Breakdown and Potential Hazards
The TMD has provided a detailed forecast across various regions, highlighting specific areas likely to experience the most severe weather:
Northern Thailand
Expect thunderstorms to affect approximately 70% of the northern region, with some locations anticipating heavy to very heavy rainfall. Provinces such as Mae Hong Son, Chiang Rai, Tak, Phitsanulok, and Phetchabun are specifically mentioned as likely to receive significant precipitation. Daytime temperatures are predicted to range between 32 and 35 degrees Celsius, with lows between 23 and 27 degrees Celsius. Winds will be from the southwest at 10 to 20 kilometers per hour.
Northeastern Thailand
Similar to the north, 70% of the northeastern region is forecast to experience thunderstorms, particularly in the upper and eastern parts. Bueng Kan, Sakon Nakhon, Nakhon Phanom, and Mukdahan are identified as areas prone to heavy rainfall. High temperatures are expected to reach 33 to 35 degrees Celsius, with lows from 23 to 26 degrees Celsius. Southwest winds will blow at speeds of 10 to 25 kilometers per hour.
Central Thailand
The central region anticipates thunderstorms covering about 60% of the area, with a focus on heavy rain in the western sections. Temperatures are expected to peak between 34 and 36 degrees Celsius, with overnight lows ranging from 23 to 26 degrees Celsius. Southwest winds will be present at 10 to 25 kilometers per hour.
Eastern Thailand
The eastern provinces are forecast to see thunderstorms across 70% of the region, with potential for heavy to very heavy rainfall. Temperatures will be notably cooler, with highs between 28 and 34 degrees Celsius and lows from 24 to 28 degrees Celsius. This region will experience stronger southwest winds, blowing at 20 to 35 kilometers per hour. Sea waves along the coast are expected to reach around 2 meters, potentially exceeding 2 meters in areas with thunderstorms.
Southern Thailand (East Coast)
The southeastern coast faces a 40% chance of thunderstorms, with heavy rain likely in the northern parts of this coastal area. High temperatures are projected between 32 and 36 degrees Celsius, and lows between 23 and 25 degrees Celsius. Sea waves are anticipated to be between 1 and 2 meters, rising above 2 meters during stormy conditions.
Southern Thailand (West Coast)
The southwestern coast also has a 40% probability of thunderstorms, with some areas expecting heavy rainfall. Temperatures will range from 28 to 35 degrees Celsius for highs and 23 to 27 degrees Celsius for lows. Notably, waves along the upper part of this coast could reach 2 to 3 meters, and potentially exceed 3 meters in thunderstorm zones.
Bangkok and Vicinity
The capital city and its surrounding areas are forecast to experience thunderstorms covering approximately 40% of the region. High temperatures are expected to be between 28 and 35 degrees Celsius, with lows from 23 to 27 degrees Celsius. Southwest winds will blow at 10 to 25 kilometers per hour.
Sea Conditions and Maritime Warnings
The Andaman Sea is expected to experience significant wave activity, with heights ranging from 2 to 3 meters, and potentially exceeding 3 meters in areas affected by thunderstorms. The upper Gulf of Thailand will see waves of about 2 meters. Mariners, particularly those operating ships in these areas, are advised to exercise extreme caution and actively avoid thunderstorm zones. For small boats operating in the upper Andaman Sea, it is strongly recommended to remain ashore during the warning period to ensure safety.
Advisory for Residents
The Thai Meteorological Department urges all residents, especially those in the northern, northeastern, and eastern parts of the country, to remain vigilant and prepared for the potential impacts of heavy rainfall. This includes the risk of flash floods, rapid forest runoff, and overflowing riverbanks, particularly in low-lying areas, near foothills, and along waterways. Residents are advised to monitor weather updates closely and plan outdoor activities with caution while the warning is in effect.
