The National Environment Agency (NEA) of Singapore said on Sunday that the country could experience slightly hazy conditions in the next few days if hotspot activities increase in southern Sumatra and the winds become unfavourable.
NEA said in an advisory that the prevailing winds are forecast to blow from the south or southwest direction. It also said that the weather conditions in southern Sumatra will be relatively dry.
The advisory added that although 28 hotspots were detected on Sunday mainly in southern Sumatra but no visible smoke plume or haze was observed in the vicinity of the hotspots.
The Pollutant Standards Index (PSI) for the next 24 hours is forecast to be in the moderate range. The 24-hr PSI was at 51-55 as at 5 pm on Sunday.
The index incorporates six types of pollutants such as sulphur dioxide, particulate matter that is 2.5 micrometres in diameter or smaller (PM2.5), particulate matter that is 10 micrometres in diameter or smaller (PM10), ozone, nitrogen dioxide and carbon monoxide.
Among all these six pollutants, PM2.5 is considered to be highly hazardous. The small size of the particles of PM2.5 enters the human lungs more easily than the others.
The advisory said thundery showers are also expected on Monday late morning and early afternoon in Singapore.
Saying about the air quality forecast for the next day, NEA said that everyone can continue with their normal activities.
People who do not feel well, especially the elderly people and children and also people with chronic heart or lung conditions should seek medical attention.
Earlier in August, Singaporeans experienced a burning smell as haze from central Sumatra was blown in, increasing the 24-hour PSI up to an unhealthy range.