Big change within a day

People played basketball at Mountbatten Community Club in Jalan Satu on Thursday at 5.30pm (left, foreground), despite the air quality being in the very unhealthy range - the 24-hour Pollutant Standards Index (PSI) at 6pm was 204-248. At 4am yesterday, the 24-hour reading went into the hazardous range of above 300. The skies became clearer yesterday (middle photo taken at 3.30pm; photo on right taken at 6.35pm), with the 24-hour PSI back in the very unhealthy range at 1pm. This was because the denser haze from Sumatra, Indonesia, that affected Singapore overnight had shifted slightly away. Hazy conditions can still be expected today, said the National Environment Agency. ST PHOTOS: DESMOND WEE

A version of this article appeared in the print edition of The Straits Times on September 26, 2015, with the headline 'Big change within a day'. Print Edition | Subscribe