Hazy conditions persist as PSI remains unhealthy across Singapore

SINGAPORE – Hazy conditions across Singapore continued overnight, with the 24-hour Pollutant Standards Index (PSI) for all regions staying within the unhealthy range and the one-hour PM2.5 readings largely within the elevated range.

At 6am on Oct 14, the 24-hour PSI reading stood at 143 in the central region, 107 in the north, 123 in the south, 142 in the east and 145 in the west.

Air quality is considered unhealthy when the PSI – a 24-hour rolling average of six key air pollutants – is in the range of 101 to 200.

The hourly PM2.5 readings – measured in micrograms per cubic m and used as a gauge for current air quality – were in the elevated zone across the island at 6am: central (96), north (60), south (74), east (91) and west (82).

PM2.5 scores from 0 to 55 represent normal values, those between 56 and 150 indicate an elevated concentration of fine particles, while those between 151 and 250 are considered high.

The PM2.5 reading in the east briefly dropped out of the elevated range at 5am, with a reading of 54.

In its daily haze advisory in the evening of Oct 13, the National Environment Agency (NEA) forecast the PSI for Singapore to be in the unhealthy range for the next 24 hours.

It said: “Moderate to dense smoke plumes were observed from fires in Kalimantan and southern Sumatra. Smoke haze was observed drifting towards Singapore under the prevailing south-easterly winds.”

While some showers are expected over Singapore and parts of the surrounding region, dry conditions are forecast to persist over parts of southern Sumatra and Kalimantan, NEA said.

For the first time since October 2023, air quality in Singapore breached unhealthy levels on Sept 4. The NEA started issuing daily haze advisories since the evening of that day.

The PSI reached a peak for 2026 on Oct 9, reaching 192 in the central region between 5pm and 8pm.

Similarly, the highest hourly PM2.5 reading to date in 2026 – 171 – was recorded in the west at 2am that same day.

The haze task force announced on the evening of Oct 9 that, among other measures, it will distribute N95 masks to eligible Singaporeans when air quality hits “very unhealthy” levels.

Such levels are denoted by a PSI reading of between 201 and 300.