Singapore haze worsens as central region’s air quality nears 2026 high, smoke from Indonesia continues to drift in

Singapore's air quality remained severely polluted early Monday morning as the haze situation showed no signs of improving, according to The Straits Times. The central region's 24-hour Pollutant Standards Index (PSI) hit 166 at 8am, just one point shy of the year's peak of 167 on September 29. The west recorded a PSI of 161, while the south, east, and north regions measured 145, 140, and 113 respectively.

Any PSI between 101 and 200 is classified as unhealthy, and Singapore's air quality had remained unhealthy throughout the past 24 hours, with some regions briefly dropping into the moderate range overnight. By 2am, however, all five regions had again reached the unhealthy level. The situation was especially concerning in the west, where PM2.5 readings - a measure of fine particulate matter - reached 152 at 8am, placing the air quality in the high pollution band.

PM2.5 readings between 56 and 150 are considered elevated, while readings between 151 and 250 fall into the high band. Singapore's National Environment Agency had warned in a daily advisory the previous evening that air quality could remain in the high moderate to mid-unhealthy range due to smoke plumes drifting from southern and central Sumatra and West Kalimantan in neighboring Indonesia.

Dry conditions were also expected to persist in those Indonesian territories, raising the likelihood of ongoing haze.