Unhealthy air returns to Asia's richest country as smoke blows in from abroad

Singapore's capital region experienced an unhealthy air quality index on Monday, as smoke from wildfires abroad infiltrated the city-state. The 24-hour Pollutant Standards Index (PSI) peaked at 108 around 2 p.m., just hours after crossing into the unhealthy range at 102 at noon. Across the island, one-hour PM2.5 concentrations surged to 113 in the central region at 10 a.m., with the ASEAN Specialised Meteorological Centre attributing the haze to transboundary smoke emanating from nearby regions.

Southeast winds were forecast to dominate, with the exception of parts of Borneo where conditions would be light and variable. Thick haze was reported over central and southern Sumatra, as well as West and Central Kalimantan, with scattered hotspots in southern Sumatra and parts of Sarawak and Peninsular Malaysia. The haze episode marked the first time the PSI had entered the unhealthy range since October 2023.

Singapore's National Environment Agency (NEA) had issued daily advisories following the activation of its Haze Task Force response plans. The agency forecast the index to remain in the moderate to low unhealthy range over the next day, attributed to smoke plumes drifting from fires in Kalimantan and further observed over southern Sumatra.

Southeast Asian authorities described this as the country's most intense wildfire season in 11 years, with emissions reaching 19.7 million metric tons, significantly more than the global average.

In response to the haze, Singapore's NEA advised healthy individuals to limit prolonged or strenuous outdoor activities, while the elderly, pregnant women, and those with chronic lung or heart conditions were advised to avoid outdoor exertion altogether.