In general, cleaner air flowed into Sri Lanka from the southwestern direction during the past week, contributing to generally favorable air quality conditions. However, on 27 May, Trincomalee recorded a daily average AQI value of 163, which falls within the “Unhealthy” category. On 25 and 26 May, Trincomalee recorded daily average AQI values of 114 and 125, respectively, which fall within the “Unhealthy for Sensitive Groups” category.

This increase in AQI levels at Trincomalee may have been influenced by localized sources, such as open burning, construction activities, or other local emissions, as cleaner air was generally being transported into Sri Lanka by prevailing southwesterly winds.

The remaining days of the week recorded “Moderate” and “Good” daily average AQI values. Trincomalee recorded the highest daily average AQI value during the week.

Considering the weekly average AQI values, Akurana, Digana, Nuwara Eliya, Chilaw, Kalawana, Trincomalee, and Anuradhapura recorded “Moderate” air quality, while all other monitored locations recorded “Good” weekly average AQI values.

Weekly Air Quality Index (AQI) Levels: 

• Moderate (AQI 51-100): Akurana, Digana, Nuwara Eliya, Chilaw(CEA), Kalawana, Trincomalee, Anuradhapura
• Good (AQI 0-50): Colombo, Kurunegala, Norochcholai, Mirihana, Negombo, Battaramulla, Ambalantota, Mannar, Jaffna