Haze update Sept 20: Air quality in central Singapore remains moderate, 24-hour PSI forecast moderate to low-unhealthy
Air quality in Singapore has improved throughout Sunday (Sept 20), with only central Singapore recording a 24-hour Pollutant Standards Index (PSI) reading in the unhealthy range at 6pm. Earlier on Sunday, the eastern and western regions joined central Singapore in that range before returning to the moderate range at 9am and 12pm respectively.At 6pm, PSI ranged from 71 to 102 — in the moderate to unhealthy range — with central Singapore recording the highest reading of 102.Meanwhile, the one-hour PM2.5 is in the normal band for all regions except for central Singapore, which has a concentration reading of 60µg/m3 — in the elevated band.In its daily haze update on Sunday evening, the National Environment Agency (NEA) said the country's 24-hour PSI forecast is expected to remain in the moderate to low-unhealthy range due to the prevailing winds blowing from the southeast, which has brought smoke haze from Sumatra to Singapore.It also noted that moderate to dense smoke plumes were observed from fires in Kalimantan.