Singapore, 17 September 2019 – There has been a slight deterioration in the hazy conditions in Singapore since late morning today. This is due to increased haziness over southern Sumatra which has been blown in by the prevailing winds. For the rest of the day, hazy conditions are expected to persist and the prevailing winds are forecast to blow from the south-southeast. As at 4pm, the 24-hr PSI was between 91-102, in the high end of Moderate range and low end of Unhealthy range, and the 1-hr PM_2.5 was 73 - 90 µg/m³, in Band II (Elevated).

 2          A total of 109 hotspots were detected in Sumatra today. The reduced count from the 233 detected yesterday was due to a partial satellite pass¹. Moderate to dense smoke haze continued to be observed in the central and southern provinces of Riau, Jambi, South Sumatra and Lampung. Some of the smoke haze has continued to be blown by the prevailing winds to affect parts of Peninsular Malaysia and Singapore.

3         For the next few days, the weather in Singapore and Sumatra is forecast to remain generally dry, and the prevailing winds are forecast to blow mainly from the southeast or south. The hotspot activities in Sumatra are expected to persist under the prevailing dry conditions. Singapore may continue to experience hazy conditions. For the next 24 hours, the 1-hr PM_2.5 concentration readings are expected to fluctuate between Band I (Normal) and Band II (Elevated). The 24-hr PSI is forecast to range between the high end of Moderate range and the low end of Unhealthy range, and depending on wind conditions, may enter the mid-section of the Unhealthy range if denser haze from Sumatra is blown in.

4          NEA is monitoring the situation closely and will provide further updates when necessary.

5        The health impact of haze is dependent on one’s health status, the PSI level, and the length and intensity of outdoor activity. Reducing outdoor activities and physical exertion can help limit the ill effects from haze exposure. Given the air quality forecast for the next 24 hours, healthy persons should reduce prolonged or strenuous outdoor physical exertion. The elderly, pregnant women and children should minimise prolonged or strenuous outdoor physical exertion, while those with chronic lung or heart disease should avoid prolonged or strenuous outdoor physical exertion. Persons who are not feeling well, especially the elderly and children, and those with chronic heart or lung conditions, should seek medical attention.

6          Air quality indicators and health advisories during periods of transboundary haze refer primarily to the 24-hour PSI. There are no accompanying health advisories for any other air quality indicators. In addition, the main air pollutant during the haze season is PM_2.5. Hence, the 1-hour PM_2.5 concentration readings are a good indicator of the current air quality. Use this for immediate activities like going for a jog.

7          For updates, visit our NEA website (www.nea.gov.sg), MSS website (www.weather.gov.sg), the haze microsite (www.haze.gov.sg), mobile apps (myEnv and Weather@SG) or follow us on NEA Facebook (www.facebook.com/NEASingapore) and NEA Twitter (@NEAsg). For information on the distribution of hotspots detected over the past fortnight in the region, please refer to the ASEAN Specialised Meteorological Centre (ASMC) website at asmc.asean.org.

^[1] A partial satellite pass occurs when the satellite field of view covers only part of a region of interest as the satellite orbits the earth.