As of June 1, 2025, Thailand has officially entered its rainy season, marking the transition from the hot summer months. The Thai Meteorological Department (TMD) confirmed that the rainy season began in late May and is expected to continue through October in the northern, northeastern, and central regions, while the southern regions may experience heavy rainfall until mid-January.

This seasonal shift is characterized by the onset of the southwest monsoon, which brings increased moisture and rainfall across the country. In Bangkok, for example, the weather forecast indicates considerable cloudiness with periods of rain, with temperatures ranging from 26°C to 35°C over the next week .

Residents are advised to stay informed about weather conditions, as the rainy season can lead to flash floods, especially in low-lying areas and regions with poor drainage systems. It’s also prudent to prepare for possible disruptions due to heavy rainfall and storms.