Bangkok’s Air Quality Information Centre forecasts a higher risk of PM2.5 build-up from December 28-30 and poor ventilation on December 31-January 1, with conditions improving on January 2-3.
The Bangkok Air Quality Information Centre has issued an updated outlook for PM2.5 levels over the New Year period, covering December 26, 2025 to January 3, 2026.
PM2.5 outlook
✅ December 26-27
Air ventilation remains relatively good, ranging from fair to good, with overall PM2.5 levels not expected to be high.
⚠️ December 28-30
Ventilation is forecast to weaken to a relatively low level, increasing the risk of PM2.5 accumulation, especially during the evening-to-morning period.
⚠️ December 31-January 1
Ventilation is expected to remain poor. Heavy traffic or large numbers of outdoor activities could push pollution levels higher in some areas.
🌤️ January 2-3
Ventilation is expected to improve, with PM2.5 levels gradually easing.
High-risk periods to watch
- 6.00pm-9.00am
- Inner-city areas and downwind parts of Bangkok
- Days with poor ventilation combined with heavy traffic
Residents can monitor real-time air quality via the AirBKK app. At-risk groups—including young children and older people—are advised to take extra care and avoid outdoor activities when pollution levels rise.