Haze in Singapore: PSI in central region back in the unhealthy range

Hazy conditions seen from Orchard on Sept 18 at 5.10 pm.

ST PHOTO: KELVIN CHNG

Published Sep 19, 2026, 01:02 PM

Updated Sep 19, 2026, 01:03 PM

SINGAPORE – The air quality in Singapore deteriorated on Sept 19 with the 24-hour Pollutant Standards Index (PSI) in the central region crossing into the unhealthy region again.

The 24-hour PSI reading in the area was 102 at 1pm. Air quality is considered unhealthy when the 24-hour PSI is in the range of 101 to 200, during which the NEA advises the public to reduce outdoor activities. PSI readings of 51 to 100 are considered moderate, while values of zero to 50 are in the “good” range. The hourly PM2.5 readings, which indicate the current concentrations of fine particulate matter, skyrocketed in the central region at 11am on Sept 19, moving from 67 to 117.

It increased further to 149 at noon, before falling to 141 at 1pm.

PM2.5 readings are considered elevated if they fall between 56 and 150, and high if they are between 151 and 250. The NEA has advised the public to refer to the hourly PM2.5 reading if they are considering immediate activities and 24-hour PSI one to plan for the day ahead.

The central region includes the Thomson, Marymount, Sin Ming, Ang Mo Kio, Bishan, Serangoon Gardens, MacRitchie and Toa Payoh areas, according to the NEA website.

The air quality had begun deteriorating late on Sept 18, with the PSI reading at 76 at 9pm before creeping up again overnight and crossing the 101 threshold at 1pm on Sept 19.

In its daily advisory on Sept 18, the NEA said smoke plumes from forest fires in Kalimantan were observed to be drifting towards Singapore. Some smoke plumes were also observed in southern Sumatra.

Dry conditions are forecast to continue over parts of southern Sumatra and Kalimantan and smoke haze might affect Singapore as the prevailing winds are expected to blow from the east-south-east or south-east.

The 24-hr PSI was forecast to be in the high moderate to low unhealthy range, added the NEA.

The PSI crossed into the unhealthy range two weeks ago, hitting 101 in central Singapore on the morning of Sept 4 . In the days that followed, readings in the central, eastern and western parts of Singapore occasionally crossed into the unhealthy range.

September’s developments mark the first time since October 2023 that the PSI in Singapore hit unhealthy levels because of haze, with the authorities earlier warning of the risk of haze between June and October as a result of warmer and drier conditions brought on by both El Nino and the Indian Ocean Dipole.

National Environment Agency

9月18日下午5点10分，从果园看到的雾霾天气。

《海峡时报》摄影：KELVIN CHNG

发布于 2026 年 9 月 19 日下午 1:02

更新于2026年9月19日下午1:03

新加坡——9月19日，新加坡空气质量恶化，中部地区的24小时污染物标准指数（PSI）再次进入不健康区域。

下午1点，该地区的24小时空气污染指数（PSI）为102。当24小时PSI在101至200之间时，空气质量被认为是不健康的，此时国家环境局（NEA）建议公众减少户外活动。PSI读数在51至100之间被认为是中等空气质量，而0至50则属于“良好”范围。9月19日上午11点，中部地区的PM2.5小时浓度（反映细颗粒物浓度）急剧上升，从67升至117。

中午时分，感染人数进一步上升至 149 人，下午 1 点降至 141 人。

PM2.5读数在56至150之间为升高，在151至250之间为高。国家环境局建议公众在考虑近期活动时参考每小时的PM2.5读数，并在计划未来一天的活动时参考24小时空气污染指数（PSI）。

根据国家环境局网站的信息，中心区域包括汤申、玛丽蒙、信明、宏茂桥、碧山、实龙岗花园、麦里芝和Toa Payoh地区。

空气质量从 9 月 18 日晚些时候开始恶化，晚上 9 点的 PSI 读数为 76，之后一夜之间再次缓慢上升，并在 9 月 19 日下午 1 点超过了 101 的阈值。

新加坡国家环境局（NEA）在9月18日的每日公告中表示，观测到加里曼丹森林火灾产生的烟雾正向新加坡方向飘移。苏门答腊南部也观测到一些烟雾。

预计苏门答腊南部和加里曼丹部分地区将持续干燥天气，由于盛行风预计来自东南偏东或东南方向，烟雾可能会影响新加坡。

国家环境局补充说，预计24小时PSI指数将处于高、中、低不健康范围。

两周前，新加坡空气污染指数（PSI）进入不健康范围，9月4日上午，新加坡中部地区的PSI达到101。在接下来的几天里，新加坡中部、东部和西部地区的PSI读数偶尔也会进入不健康范围。

9 月份的情况标志着自 2023 年 10 月以来，新加坡的空气污染指数 (PSI) 首次因雾霾达到不健康水平。此前，当局曾警告称，由于厄尔尼诺现象和印度洋偶极子现象带来的气候变暖和干燥，6 月至 10 月期间存在雾霾风险。

国家环境局