SINGAPORE - Expect hazy conditions seen in Singapore on Friday (Oct 23) to persist throughout Saturday (Oct 24), as haze from Kalimantan spread to the surrounding region.

As at 11pm, the 24-hour Pollutant Standards Index (PSI) was 148-174, in the unhealthy range. The three-hour PSI, which is not tied to a health advisory, was 223.

This was up from a 24-hour PSI of 131-153 and a three-hour PSI of 244 at 8pm.

The 24-hour PSI for the next 24 hours is expected to be in the mid to high sections of the unhealthy range (101-200), the National Environment Agency (NEA) said in an update at 5pm on Friday. It could enter the low end of the very unhealthy range if denser haze is blown in.

Widespread dense haze is observed over Kalimantan, and some of the haze continues to spread to the surrounding sea areas south-east of Singapore, and is being blown in by the prevailing south-easterly winds, said NEA.

"Only one hotspot was detected in Sumatra today. The low hotspot count was due to partial satellite pass and cloud cover over parts of Sumatra. Moderate to dense smoke haze is still persisting in central and southern Sumatra," it added.

Given the air quality forecast for the next 24 hours, healthy people 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.

People who are not feeling well, especially the elderly and children, and those with chronic heart or lung conditions, should seek medical attention.

For updates, visit NEA website (www.nea.gov.sg), the haze microsite (www.haze.gov.sg), follow us on NEA Facebook (www.facebook.com/NEASingapore) and NEA Twitter (@NEAsg), or download the myENV app.