Heavy rain advisory issued for Thailand as monsoon intensifies

The Meteorological Department has issued a weather warning of widespread thunderstorms and isolated heavy rainfall in the northeast, the central plains, Greater Bangkok, the east and the southwest coast.

A moderate southwest monsoon currently blankets the Andaman Sea, the Gulf of Thailand and the country, coupled with a low-pressure cell hovering over northern Vietnam. Residents have been urged to brace for flash floods, severe runoffs and dangers associated with accumulated rainfall over the next 24 hours.

Conditions are expected to worsen significantly from June 28 to July 3, with a dramatic surge in rainfall across the country. The weather bureau warns that a monsoon trough will move across the north and extreme northeast, while the prevailing southwest monsoon over the seas will strengthen. This will trigger torrential rain and potential flooding, particularly in the eastern provinces and the southwest coast.

Maritime conditions will also deteriorate during the forecast period. Wave heights in the northern Andaman Sea are predicted to reach 2 to 3 meters, and over 3 meters in stormy areas. Mariners in both the Andaman Sea and the Gulf of Thailand are strongly advised to navigate with extreme caution and avoid operating vessels in thunderstorm zones.

For the immediate 24-hour forecast, ending tomorrow morning, Greater Bangkok, the central region and the east will see thunderstorms covering 60% of their areas, with isolated heavy downpours. The southwest coast faces the highest risk today, with thunderstorms projected to blanket 70% of the area, affecting Ranong, Phang Nga, Phuket and Krabi. Meanwhile, the north and northeast are expected to see rain over 40% of the area.