Winds bring haze back to Singapore: Hourly PM2.5 in elevated band islandwide

Singapore's "oxygen pass" expired on Friday (July 23) afternoon, as prevailing winds brought smoke haze back from fires in Indonesia's Kalimantan and Sumatra.

At 1pm, hourly PM2.5 was in the elevated band (56 to 150µg/m3) in all five regions.

Concentration readings ranged from 56 in northern Singapore to 84 in southern Singapore.

Meanwhile, the 24-hour Pollutant Standards Index (PSI) remains in the good-to-moderate range (0 to 100).

It is expected to climb into the unhealthy range if PM2.5 readings remain elevated over the next few hours.

Checks on the Meteorological Service Singapore's weather site show that winds are predominantly from the south, making the haze situation not unexpected.

In its daily haze situation update on Thursday evening , the National Environment Agency (NEA) had said that the country's 24-hour PSI forecast is between 101 and 150 — in the unhealthy range.

Given the prevailing south-easterly or southerly winds, smoke haze may still be transported towards Singapore on Friday and Saturday, it added.

The haze condition is expected to improve on Sunday due to showers and favourable winds, NEA added.

Eligible Singaporeans can collect a second pack of two N95 haze masks from community clubs or mask vending machines from today (Oct 23).

新加坡的“氧气通行证”于周五（7月23日）下午到期，因为盛行风将印度尼西亚加里曼丹岛和苏门答腊岛的火灾产生的烟雾带回了新加坡。

下午 1 点，所有五个地区的 PM2.5 小时浓度均处于较高水平（56 至 150µg/m3）。

浓度读数从新加坡北部的 56 到新加坡南部的 84 不等。

与此同时，24 小时污染物标准指数 (PSI) 仍处于良好至中等水平 (0 至 100) 范围内。

如果未来几个小时内 PM2.5 读数持续偏高，预计该指标将攀升至不健康范围。

查看新加坡气象局的天气网站可知，风向主要来自南方，因此出现雾霾情况并不出乎意料。

国家环境局 (NEA) 在周四晚间发布的每日雾霾情况更新中表示，该国 24 小时 PSI 指数预测在 101 至 150 之间——处于不健康范围内。

报告还指出，鉴于目前盛行的东南风或南风，周五和周六仍有可能向新加坡输送烟雾。

国家环境局补充说，由于降雨和有利的风向，预计周日雾霾情况将有所改善。

符合资格的新加坡人从今天（10 月 23 日）起可以在民众俱乐部或口罩自动售货机领取第二包两只装的 N95 防雾霾口罩。