SINGAPORE — With a “sharp increase” in the number of hotspots detected in parts of Indonesia over the past few days, expect “slightly hazier” days ahead depending on wind conditions, the National Environment Agency (NEA) warned today (Aug 26). The latest number of hotspots as of today was 488, of which 267 are in Riau province and 66 in South Sumatra. The NEA also said “moderate to dense smoke plumes” were observed over some of the hotspots in central Sumatra. Last Tuesday, the number of hotspots detected in Sumatra was 29. The NEA said its Chief Executive Officer Ronnie Tay has written and spoken to his Indonesian counterparts to register Singapore’s concerns over the sharp increase in hotspot counts, and has “sought an urgent update from the Indonesians on the situation”. Calling the spike in hot spots “an exercise in frustration”, Minister for the Environment and Water Resources Vivian Balakrishnan said, Singapore has been spared so far because of the wind direction. “We remain at risk. Have to keep up the pressure on the Indonesian authorities and companies to do the right thing for the sake of their own citizens and ours,” he wrote on his Facebook page tonight. As of 7pm, the 24-hour Pollutant Standards Index reading was 24 to 32, and the 24-hour PM2.5 reading was 12-15 µg/m3. The NEA said that dry weather conditions are expected to prevail in central and southern Sumatra, while the low-level winds over Singapore are expected to blow from the south or southeast. “Should the winds weaken and blow from the southwest over the next few days, there is a possibility that Singapore could experience slightly hazy conditions,” the agency said in a statement. The NEA said thundery showers are expected tomorrow in the late morning and early afternoon. Given the favourable wind conditions, the 24-hour PSI reading until 6pm tomorrow is expected to be in the “Good” band — 50 and below — and the 24-hour PM2.5 reading is expected to be slightly elevated. The ASEAN Specialised Meteorological Centre (ASMC), hosted by the Meteorological Service Singapore, has placed Sumatra on Alert Level 2 — out of three levels — of its regional warning system for the fire and haze situation. Level 2 is activated when 150 hotspots or more are detected on two consecutive days, with dry weather conditions persisting and prevailing winds blowing towards other ASEAN countries. The alert levels are issued to the interim ASEAN Coordinating Centre for Transboundary Haze Pollution which in turn disseminates it to the ASEAN member countries. The public — including the elderly, pregnant women, children and those with chronic medical conditions — can still continue with normal activities for the day. The NEA will update the public if there are any changes in the haze situation. Last Tuesday, the three-hour PSI readings crept up to hit the moderate range of 56 in the afternoon, but dipped back to the good range in the evening, as a result of wind conditions.