Singapore's air quality reached unhealthy levels on Sunday, after days of relatively clear skies, with the three-hour Pollutant Standards Index (PSI) hitting 110 at 4 p.m., local TV Channel NewsAsia reported on Sunday.
The three-hour PSI reading moved up sharply after 11 a.m., edging past 100 to 104 at 3 p.m., after it remained below 70 for the previous few hours, the local media said.
Last month, the Meteorological Service Singapore said that there will likely be more rain over Singapore and the surrounding region in the coming weeks, when the traditional dry season comes to an end for the year.
The agency added that Singapore may experience occasional slight haze on some days due to the accumulation of particulate matter in the air under light wind conditions.
"The Inter-Monsoon period normally lasts from October to November, and is characterized by more rainfall and light winds that are variable in direction. The increased rainfall will help alleviate the hotspot and haze situation in Sumatra and Kalimantan, " it said.