Singapore's 24-hour PSI forecast moderate; unfavourable winds on Thursday, Friday could bring smoke haze from Indonesia

Except for a brief spike in the northern region at 4pm, when hourly PM2.5 briefly entered the elevated band (56 to 150µg/m3), air quality in Singapore on Tuesday (Oct 27) was generally suitable for normal activities.

At 9pm, hourly PM2.5 readings were in the normal band across all five regions.

The highest readings of 31 were recorded in central and eastern Singapore, while the northern region had the lowest reading of 22.

Meanwhile, the 24-hour Pollutant Standards Index (PSI) readings ranged from 63 in the eastern and southern regions to 73 in western Singapore.

A PSI reading from 0 to 100 is in the good-to-moderate range.

Haze and weather outlook till Friday

In its daily haze situation update on Tuesday evening, the National Environment Agency (NEA) said the PSI forecast for Wednesday is between 60 and 90 — in the moderate range.

"For (Wednesday), the winds are forecast to blow from the east-northeast. Showers are expected over Kalimantan, Sumatra and Singapore and surrounding region which could continue to help with the haze situation."

But unfavourable winds — from the east-southeast or south-southeast — on Thursday and Friday could transport smoke haze from southern Sumatra.

Showers forecast over the region could help to lower the risk of haze, NEA said.

Members of the public should check the latest hourly PM2.5 concentration readings before taking part in outdoor activities.

除了下午 4 点北部地区 PM2.5 小时浓度短暂飙升（56 至 150µg/m3）外，周二（10 月 27 日）新加坡的空气质量总体上适合正常活动。

晚上9点，五个地区的PM2.5小时读数均在正常范围内。

新加坡中部和东部地区的读数最高，为 31，而北部地区的读数最低，为 22。

与此同时，新加坡东部和南部地区的 24 小时污染物标准指数 (PSI) 读数为 63，西部地区的读数为 73。

PSI读数在0到100之间属于良好到中等范围。

周五之前的雾霾和天气预报

国家环境局（NEA）在周二晚间发布的每日雾霾情况更新中表示，周三的PSI指数预计在60到90之间，属于中等范围。

“预计（周三）风向将转为东北偏东。加里曼丹、苏门答腊、新加坡及周边地区将有阵雨，这可能有助于缓解雾霾情况。”

但周四和周五来自东南偏东或东南偏南的不利风向可能会将苏门答腊南部的烟霾吹过来。

国家环境局表示，预计该地区将出现阵雨，这可能有助于降低雾霾风险。

公众在参加户外活动前，应查看最新的PM2.5每小时浓度读数。