Air quality returns to unhealthy range in central Singapore

Air quality returns to unhealthy range in central Singapore As of 9pm, the 24-hour Pollutant Standards Index in Singapore's central region was 102. SINGAPORE: Air quality in the central region of Singapore returned to the unhealthy range on Thursday (Sep 17) evening after a day. The 24-hour Pollutant Standards Index (PSI) in the region hit 102 at 9pm, crossing into the unhealthy band. Air quality remained in the moderate range for the other regions of the country. PSI readings have dipped in and out of the unhealthy range over the past two weeks. On Tuesday, all five regions of Singapore recorded unhealthy air quality levels, marking the first time this has happened since September 2019. On Thursday, the National Environment Agency (NEA) said in its daily haze advisory that the 24-hour PSI was forecast to be in the high moderate to low unhealthy range. It added that as the prevailing winds were blowing from the southeast to southwest on Thursday, some smoke haze had drifted from southern and central Sumatra towards Singapore. There were also smoke plumes observed over southwestern Kalimantan. "Dry conditions are expected to continue over southern Sumatra and southern Kalimantan. With the prevailing winds forecast to blow from the southeast to southwest, there is a risk of smoke haze affecting Singapore." The 24-hour PSI spiked into the unhealthy range in central Singapore on Sep 4 for the first time since 2023, prompting NEA to start providing daily haze advisories from that evening. The unhealthy PSI band runs from 101 to 200, while a reading is considered "very unhealthy" if it is between 201 and 300, and "hazardous" if it is above 300.