Thailand will officially begin its rainy season on Thursday, according to the country’s Meteorological Department, which has forecast that rainfall levels for 2025 will be slightly below those recorded last year.
The department projects overall rainfall this year to be around 5% above the long-term average, though still less than in 2024. Rainfall across the northern and northeastern regions is expected to be 5% to 10% above average through July, while other areas may see more moderate levels.
Between mid-June and July, a temporary decrease in rainfall is expected in the northern and northeastern provinces, as well as in parts of the central plains. The Meteorological Department has advised farmers without access to irrigation systems to use water sparingly during this dry spell.
From August to October, the rainy season is forecast to intensify, bringing a higher risk of storms, flash floods, and river overflows in flood-prone areas. The Meteorological Department has also indicated that one or two tropical storms may affect the northern and northeastern regions during this period.
Rainfall is expected to return to average levels in most parts of the country from August through December, with the exception of the eastern coast of the southern region, where precipitation could be about 10% below average. The department also noted that the El Niño–Southern Oscillation (ENSO) climate pattern will likely remain neutral between September and November, contributing to slightly above-average rainfall in some areas.
Officials from the Meteorological Department, including Director-General Dr. Sukanyanee Yawinyacharn, shared these projections during a recent briefing.
