Air quality across all five regions of Singapore entered the unhealthy range on Sept 15, 2026, marking a significant worsening of regional haze conditions driven by smoke plumes from forest fires in Kalimantan and southern Sumatra.
An Island-Wide Grip of Unhealthy Air
Singapore woke to a familiar, unwelcome blanket of gray on Sept 15, 2026. For the first time since October 2023, the PSI in Singapore hit unhealthy levels because of haze.
When the 24-hour PSI hovers between 101 and 200, the National Environment Agency (NEA) officially advises the public to reduce outdoor activities. It is a stark shift from the moderate conditions residents enjoyed just days prior. Channel NewsAsia reported that this widespread deterioration marks the first time all regions in the country entered the unhealthy range since September 2019.
Tracing the Smoke Across Maritime Southeast Asia
The culprit behind the haze sits hundreds of kilometers away. Meteorological conditions, amplified by a mix of El Niño and the Indian Ocean Dipole, have cultivated prolonged warmer and drier conditions across the region. These parched landscapes have allowed forest fires in Kalimantan and southern Sumatra to rage unchecked.
According to NEA advisories, moderate to dense smoke plumes from these Indonesian land fires have steadily drifted northward on prevailing south-east to east-southeast winds. With dry weather forecast to persist across Singapore and the surrounding region over the coming days, the agency warned that the republic will likely be affected by smoke haze.
Fine Particulate Spikes Hit Urban Centers
While the 24-hour PSI captures the broader daily trend, the fine particulate matter tells an immediate story of localized density. One-hour PM2.5 readings across most of the island largely returned to normal bounds, hovering between 32 and 44 micrograms per cubic meter by early morning on Sept 15.
However, urban density and wind patterns left certain zones exposed. The central region recorded a PM2.5 level of 66, while the west hit 59.
Looking Ahead at Regional Weather Patterns
Authorities continue to issue regular updates as shifting wind directions dictate the density of incoming smoke plumes.
Residents are encouraged to check real-time updates directly through official channels like the National Environment Agency website to manage daily exposure safely.
