Climate & Environment · Asia

Western Singapore’s 24-hour PSI reaches 230, a yearly high

Smoke from fires in Kalimantan and haze observed over Sumatra could drift toward Singapore, as the western 24-hour PSI reached 230 on Sunday, the country’s highest reading this year, highlighting the impact of cross-border smoke on air quality.

AI-assisted synthesis · Based on 5 outlets' reporting · Article text read from 1 of 5 outletsHow it's made

View timeline · 7 entries

5 outlets2 regionsLatest reporting Oct 17, 11:22 PM UTC3 min read

Coverage: Mostly CenterL 0 · C 4 · R 1

Updat3 graphic · Map data: Natural Earth Natural Earth (public domain)

What happened

Key facts

At 10am on Oct 18, 2026, western Singapore’s 24-hour PSI reached 230, a new high for Singapore this year (per CNA).
At 11am, hourly PM2.5 readings were 142 in western Singapore and 88 in the central region (per CNA).
At 11am, hourly PM2.5 readings were 54 in northern Singapore, 49 in the south and 52 in the east (per CNA).
The National Environment Agency said smoke haze from fires in Kalimantan continued moving towards Singapore on Saturday amid southeasterly winds (per CNA).
The National Environment Agency said winds could shift south or south-southeast on Sunday, possibly reducing smoke transport from Kalimantan, while haze from Sumatra could continue drifting towards Singapore (per CNA).

The brief

The 24-hour Pollutant Standards Index (PSI) in western Singapore reached 230 at 10am on Oct 18, a new high for the country this year, according to CNA. The agency’s account places the reading amid haze moving towards Singapore from Kalimantan and haze observed over Sumatra.

The west’s reading was reported alongside elevated hourly PM2.5 measurements in several parts of the city-state. At 11am, hourly PM2.5 readings stood at 142 in the west and 88 in the central region. The north recorded 54, the south 49 and the east 52. CNA reported that the 24-hour PSI readings in Singapore’s other four regions were in the unhealthy band.

These are different measures and reporting periods: the 230 figure is a 24-hour PSI reading, while the regional figures at 11am are hourly PM2.5 readings. The National Environment Agency (NEA) said smoke haze from fires in Kalimantan continued moving towards Singapore on Saturday amid southeasterly winds. The agency also said it had observed haze over Sumatra.

NEA’s account therefore identifies haze in both locations, while distinguishing the direction of smoke transport from Kalimantan from the haze observed over Sumatra. In an advisory issued on Saturday, NEA forecast that the 24-hour PSI would be in the unhealthy to very unhealthy range for Sunday.

It said winds could shift south or south-southeast on Sunday, a change that might reduce smoke moving from Kalimantan. NEA also said haze from Sumatra could keep drifting towards Singapore and that rain was likely.

CNA reported two changes to public events: The Great Eastern Women's Run, originally scheduled for Nov 1, was cancelled, and The Purple Parade was postponed to the first half of 2027. The article does not connect either event decision to a particular PSI reading or give a reason for the decisions.

Singapore’s Ministry of Health advised vulnerable groups—including elderly people, pregnant women and people with chronic heart or lung conditions—to avoid outdoor activities when hourly PM2.5 readings are in the high band, defined in the article as 151 to 250.

The west’s 11am reading of 142 was below that stated band; the advice was framed around readings reaching the specified range, rather than as a report of an individual health outcome.

Why it matters

The west’s 24-hour PSI reached 230, while the 11am hourly PM2.5 reading there was 142; these readings describe different measures and periods.
The Ministry of Health’s advice specifically concerns elderly people, pregnant women and people with chronic heart or lung conditions, and recommends avoiding outdoor activity when hourly PM2.5 reaches 151 to 250.
The Great Eastern Women's Run was cancelled, and The Purple Parade was postponed to the first half of 2027.

What to watch next

Whether the National Environment Agency’s forecast of unhealthy to very unhealthy 24-hour PSI levels for Sunday matches subsequent readings.
Whether winds shift south or south-southeast on Sunday, as the National Environment Agency said could reduce smoke transport from Kalimantan.
Whether rain occurs, as the National Environment Agency said it was likely.
The Purple Parade’s rescheduled timing in the first half of 2027.

How it's being covered

Coverage analysisShow details

6 source articles · 5 unique outlets

Outlet political mix: Mostly Center· 4 Center · 1 Right

Where the outlets are based: Asia 80% · US/Canada 20%

Outlet political mix

Mostly Center

Left

Center

Right

0 outlets

4 outlets

1 outlet

The marker shows coverage balance: each unique outlet counts once.

Geography

Where the outlets covering this story are based.

5 unique outletsDominant coverage: Asia

All5 US/CA1 · 20%Asia4 · 80%

Coverage imbalance

Coverage is currently concentrated among Center-rated outlets (4 of 5 rated sources); comparatively few Left-rated outlets have published on the event.
Coverage is currently concentrated among outlets based in Asia (4 of 5 geographically-identified sources).

How we measure coverage

How outlets' accounts compare

Updat3 does not yet have enough full reports to compare how outlets framed this story.

Timeline

Developments from this story's sources, dated background we compiled and fact-checked, and our earlier coverage. Each row says which.

1997
Fires in Indonesia sent haze across Southeast Asia, including Singapore.
Background · compiled and fact-checked by Updat3
Jun 10, 2002
The main regional framework is the ASEAN Agreement on Transboundary Haze Pollution, signed by ASEAN member states on 10 June 2002.
Background · from our historical context
Jul 1, 2002
Singapore established the National Environment Agency.
Background · compiled and fact-checked by Updat3
Jun 21, 2013
Singapore’s Pollutant Standards Index reached 401, then a record high, and NEA advised people to use N95 masks during prolonged outdoor exposure.
Background · compiled and fact-checked by Updat3
2014
Singapore also enacted the Transboundary Haze Pollution Act in 2014.
Background · from our historical context
Sep 25, 2015
On 25 September 2015, Singapore’s three-hour PSI reached 341, a hazardous reading; Indonesian fires that year burned on peatlands as well as other land.
Background · from our historical context
Sep 25, 2015
Singapore’s Pollutant Standards Index reached 341 during a haze episode.
Background · compiled and fact-checked by Updat3

How we got here

Singapore’s 2019 haze episode offers a recent precedent for cross-border smoke affecting the city-state: on 14 September, Singapore’s three-hour Pollutant Standards Index reached 154, in the unhealthy range. The episode followed fires in parts of Indonesia, including Sumatra and Kalimantan, and showed how smoke carried by winds could affect air quality across national borders.

The 2015 Southeast Asian haze was more severe. On 25 September 2015, Singapore’s three-hour PSI reached 341, a hazardous reading; Indonesian fires that year burned on peatlands as well as other land. The main regional framework is the ASEAN Agreement on Transboundary Haze Pollution, signed by ASEAN member states on 10 June 2002.