KUCHING (THE STAR/ASIA NEWS NETWORK) - The haze has returned to Sarawak, with Sri Aman town recording unhealthy air quality on Tuesday (Sept 22).

As at 11.00 am, the Air Pollutant Index (API) was 115 in Sri Aman, which is about 160km from the state capital. It was the only place in Malaysia with unhealthy air on Tuesday morning. The API in Sri Aman crossed into the unhealthy range at 4am.

A change of wind direction on Monday evening is believed to have brought the haze back.

The other parts of Sarawak state recorded moderate or healthy air quality. In Kuching, the pollution level was moderate with API at 90 at 11.00am, rising from just 44 a day earlier. Visibility was down to a mere 800m.

The API was moderate in Sibu at 74, while Miri was at 35, a healthy level.

Air quality with API readings of 0-50 is categorised as good, 51-100 (moderate), 101-200 (unhealthy), 201-300 (very unhealthy) and 301 and above (hazardous).

The Singapore-based Asean Specialised Meteorological Centre has reported "widespread smoke haze" across Kalimantan as the dry weather conditions prevailed. In Sumatra, shower activities in recent days has helped to reduced the extent of haze area.

Latest images from the satellite NOAA-18, which captures open burning larger than 10 sq m, showed 475 hotspots on Borneo on Monday.

According to the Malaysian Meteorological Department's seasonal report, there could be 20 per cent to 40 per cent less rain this month in Sarawak compared to the long term average.

"The moderate El-Nino currently experienced is expected to intensify in Sept and it may continue until early 2016 with a probability of over 90 per cent," said its weather outlook until Feb 2016.