Singapore’s air quality hit unhealthy levels islandwide on Tuesday, September 15, 2026, marking the first time all five regions in the city-state recorded such levels since September 2019. This deterioration is attributed to haze originating from wildfires in neighboring Indonesia, which has continued to spread across Southeast Asia.
According to IQAir data, Singapore ranked as the world’s sixth-most polluted city during this period, trailing Kuala Lumpur, which held the top spot. The Pollutant Standards Index (PSI) readings at 6 AM on September 15 were 104 for the north, 111 for the south, 128 for the east, 128 for the west, and 154 for the central regions, all falling within the unhealthy range (101-200).
While the 24-hour PSI remained unhealthy, one-hour PM2.5 readings largely returned to normal levels by 9 AM, with central Singapore showing a marginally elevated reading of 57 at 7 AM. The National Environment Agency (NEA) had previously forecast air quality to be in the high moderate to mid-unhealthy range for the next 24 hours and advised the public, especially vulnerable groups, to reduce strenuous outdoor activities.
