Singapore Haze Alert: Air Quality Turns ‘Worst in the World’ as Indonesian Wildfire Smoke Spreads

Singapore has issued a haze advisory for travellers as smoke from Indonesian wildfires pushes air pollution into unhealthy levels, raising health concerns ahead of the city-state’s Formula One Grand Prix weekend.

Singapore’s Meteorological Service reported on October 9 that the 24-hour Pollutant Standards Index (PSI) ranged from 134 to 192 at 5 pm, placing air quality across the island in the unhealthy category. Fine-particle pollution readings were also elevated.

The haze has spread from southern and central Sumatra, with smoke also reported over parts of Kalimantan. Prevailing winds are expected to carry more smoke towards Singapore, while dry conditions in fire-prone areas could prolong the episode.

Singapore Air Pollution Among the World’s Worst

Singapore’s air pollution climbed sharply this week as haze from regional wildfires blanketed the city-state. Global air-quality monitoring data placed Singapore among the world’s most polluted cities, with readings worsening as smoke spread across Southeast Asia.

The pollution has also affected neighbouring Malaysia. Authorities in Johor ordered around 200 schools, kindergartens and nurseries in the Batu Pahat district to close on October 7 because of haze, according to reports cited by the South China Morning Post.

Why the Haze Is Reaching Singapore

The haze is largely linked to fires in Indonesia, where prolonged dry weather has increased the risk of vegetation and land fires. Smoke can travel hundreds of kilometres, with wind direction and speed determining how quickly it reaches Singapore and where pollution accumulates.

Air quality can also vary across the island. Buildings, local wind patterns and urban heating can affect how efficiently polluted air disperses, leaving some areas with higher concentrations of fine particles than others.

The main concern is PM2.5, fine particulate matter measuring 2.5 micrometres or less. These particles can remain suspended in the air for extended periods and penetrate deep into the respiratory system.

Health Risks and Advice for Travellers

Unhealthy air quality can cause eye and throat irritation, coughing and breathing difficulties. People with asthma or other chronic lung and heart conditions, along with children, older adults and pregnant women, may need to take additional precautions.

Singapore’s National Environment Agency advises people to use hourly PM2.5 readings when deciding whether to undertake immediate outdoor activities. The 24-hour PSI forecast is more useful for planning activities for the following day.

When pollution reaches unhealthy levels, healthy people should reduce prolonged or strenuous outdoor exercise. Vulnerable groups are advised to limit such exertion further, depending on the pollution readings and their health status.

Travellers should monitor official air-quality updates, reconsider strenuous outdoor excursions during periods of elevated pollution and seek medical attention if they develop significant breathing difficulties.

Will the Haze Improve?

Some showers are forecast over Singapore and parts of the surrounding region over the weekend. However, dry conditions are expected to persist in parts of southern Sumatra and Kalimantan, meaning smoke could continue to drift towards Singapore.

The Meteorological Service has warned that the 24-hour PSI could remain in the unhealthy to low very unhealthy range. Any improvement will depend on rainfall, wind patterns and the intensity of fires across the region.

For visitors, the immediate priority is to follow local health guidance and check air-quality readings before outdoor activities. The evolving haze situation also poses a challenge for Singapore as it prepares to host major international events during the Grand Prix weekend.