Overview
- Central Singapore briefly entered the unhealthy band on Thursday when 24‑hour PSI readings reached 102 at 9pm and 103 at 10pm, marking a short spike in pollution late on Sept 17.
- Readings in the north, south, east and west regions stayed in the moderate range during the evening, so the episode was localised rather than nationwide.
- Hourly PM2.5 levels were elevated in the central region at about 93 micrograms per cubic metre at 9pm, exceeding the elevated band threshold of 56 to 150 µg/m3 and indicating short‑term health risk.
- Air quality improved overnight into the morning of Sept 18, with the central 24‑hour PSI falling back to 100 at 1am and to 97 by 7am, returning the region to the moderate band.
- The NEA links the haze to dry conditions and hotspots in southern Sumatra and southern Kalimantan, advises healthy people to cut back on prolonged or strenuous outdoor activity, urges vulnerable groups to minimise exposure, and notes that increased showers forecast later in September could ease pollution.