Bangkok warns of higher PM2.5 risk over New Year as ventilation worsens on December 28-January 1

SATURDAY, DECEMBER 27, 2025

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.

Bangkok warns of higher PM2.5 risk over New Year as ventilation worsens on December 28-January 1


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.