Haze watch: PSI remains unhealthy in 3 regions

Residents in the northern and southern regions woke up to slightly improved air quality on Wednesday (Oct 7), after 24-hour Pollutant Standards Index (PSI) reading turned high-moderate overnight.At 8am, PSI in central (130), eastern (119) and western (118) Singapore were in the unhealthy range.Meanwhile, one-hour PM2.5 in the same three regions are in the elevated band, with western Singapore recording the highest concentration reading of 80.PM2.5 concentration readings in the northern and southern regions were in the normal band. In its daily haze situation update on Tuesday evening, the National Environment Agency (NEA) said the country's 24-hour PSI forecast is expected to remain in the high moderate to mid-unhealthy range.It noted that moderate to dense smoke plumes from southern Sumatra and West Kalimantan were observed drifting towards Singapore.Data from the ASEAN Specialised Meteorological Centre shows that the number of hotspots in Kalimantan fell from 438 on Oct 5, to 178 on Oct 6.