Haze in S’pore: PSI readings across Singapore back in moderate range

Hazy conditions seen at Chinatown at about 4.30pm on Sept 20.

ST PHOTO: KELVIN CHNG

Published Sep 20, 2026, 07:08 PM

Updated Sep 20, 2026, 07:08 PM

Air quality in Singapore improved to moderate levels on Sept 20, with the central region's 24-hour PSI dropping from unhealthy to 100 by 7pm.

Hourly PM2.5 readings were mostly normal except for central Singapore, which had elevated levels at 57, prompting NEA advice on activity planning.

NEA forecasts moderate to unhealthy PSI due to dry conditions in Sumatra and Kalimantan, with haze risks linked to El Nino and Indian Ocean Dipole effects.

SINGAPORE – Air quality across Singapore is back to moderate levels on the evening of Sept 20 as the 24-hour Pollutant Standards Index (PSI) reading in the island’s central region dipped out of the unhealthy spectrum as at 7pm.

The PSI value for that area was 100 as at 7pm, down from 120 at 10am, and joined the eastern and western regions in the moderate zone, after the PSI readings for the latter two areas dropped below 101 earlier the same day.

The PSI reading in the west dropped to 92 as at 7pm, after hitting a peak of 106 at 10am on Sept 20.

In the east, the level dipped to 79 as at 7pm, after it entered the unhealthy range earlier in the day at 3am with a reading of 102.

The PSI readings in the north (71) and south (75) remained in the moderate range.

The PSI reading in the central area had been in the unhealthy range since 1pm on Sept 19, with air quality in the rest of the country remaining in the moderate range throughout the day.

Air quality is considered unhealthy when the 24-hour PSI is in the range of 101 to 200, during which the National Environment Agency (NEA) advises the public to at least 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 for the north, south, east and west areas are between 32 and 51 and in the normal zone as at 7pm on Sept 20. The PM2.5 reading for central Singapore is 57, in the elevated band.

PM2.5 readings, which indicate the current concentrations of fine particulate matter, 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 the 24-hour PSI readings to plan for the day ahead.

In its daily haze advisory on Sept 20, the NEA said the 24-hour PSI is forecast to be in the “moderate to unhealthy” range, even following afternoon showers over the northern and eastern parts of Singapore.

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

The PSI crossed into the unhealthy range just over 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 the island occasionally crossed into the unhealthy range.

The developments in September 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.

9月20日下午4点30分左右，唐人街出现雾霾天气。

《海峡时报》摄影：KELVIN CHNG

发布于 2026 年 9 月 20 日下午 7:08

更新于2026年9月20日晚上7:08

9月20日，新加坡空气质量改善至中等水平，中部地区的24小时空气污染指数（PSI）在晚上7点从不健康降至100。

除了新加坡中部地区 PM2.5 水平升高至 57 外，其他地区的每小时 PM2.5 读数大多正常，新加坡中部地区 PM2.5 水平升高，促使国家环境局建议民众制定活动计划。

国家环境局预测，由于苏门答腊岛和加里曼丹岛干旱，空气污染指数将达到中度至不健康水平，而厄尔尼诺现象和印度洋偶极子效应将带来雾霾风险。

新加坡——9月20日晚，新加坡空气质量恢复至中等水平，截至晚上7点，该岛中部地区的24小时污染物标准指数（PSI）读数已脱离不健康范围。

截至晚上 7 点，该地区的 PSI 值为 100，低于上午 10 点的 120，与东部和西部地区一起进入了中等污染区，此前东部和西部地区的 PSI 读数在当天早些时候降至 101 以下。

截至晚上 7 点，西部地区的 PSI 读数降至 92，此前在 9 月 20 日上午 10 点曾达到 106 的峰值。

东部地区，截至晚上 7 点，空气质量指数降至 79，此前在凌晨 3 点，该指数曾达到不健康范围，读数为 102。

北部（71）和南部（75）的PSI读数保持在中等范围内。

9 月 19 日下午 1 点以来，中心地区的空气污染指数 (PSI) 一直处于不健康范围，而全国其他地区的空气质量当天则保持在中等范围。

当24小时空气污染指数（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）建议公众至少减少户外活动。PSI读数在51至100之间被认为是中等的，而0至50之间的数值则属于“良好”范围。

截至9月20日晚上7点，新加坡北部、南部、东部和西部地区的PM2.5小时读数在32至51之间，处于正常范围内。新加坡中部地区的PM2.5读数为57，处于较高水平。

PM2.5 读数表示当前细颗粒物的浓度，如果读数在 56 到 150 之间则被认为是升高的，如果读数在 151 到 250 之间则被认为是高的。

国家环境局建议公众，如果考虑立即进行活动，请参考每小时的 PM2.5 读数；如果计划当天的活动，请参考 24 小时的 PSI 读数。

新加坡国家环境局在 9 月 20 日发布的每日雾霾预警中表示，即使新加坡北部和东部地区下午有阵雨，24 小时空气污染指数预计仍将处于“中度至不健康”的范围内。

预计苏门答腊南部和加里曼丹西南部部分地区将持续干燥天气，由于盛行风向预计为东南风，烟雾可能会影响新加坡。

两周多前，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，该岛中部、东部和西部地区的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。