S'pore to experience smoke haze next few days, PSI hits 145

Singapore is anticipated to encounter smoke haze over the next few days, with the 24-hour PSI expected to fall into the high moderate to mid unhealthy range, according to the National Environment Agency (NEA). A PSI value between 51 and 100 signifies a moderate range, while 101 to 200 indicates an unhealthy range. The PSI value at midnight on September 15 is 145, which falls into the mid unhealthy range.

The worsening haze is attributed to dry conditions forecasted over Singapore and the surrounding area in the coming days. The prevailing winds are expected to continue blowing from the southeast to east-southeast. Brief showers occurred over some parts of Singapore on Monday, according to the NEA.

At 6pm on Monday, the 24-hour PSI was 88 to 120, placing it in the moderate to unhealthy range. The one-hour PM2.5 concentration readings, which serve as a real-time gauge of air quality during hazy conditions, were 56 to 121, placing it in Band 2 (Elevated). The PM2.5 readings indicate the one-hour air quality during hazy conditions.

NEA attributed the air quality deterioration to smoke plumes from fires in Kalimantan drifting towards Singapore due to a shift in prevailing winds blowing from east-southeast. Some smoke haze was also observed drifting from southern Sumatra. The health impact of haze depends on an individual's health status, the PSI level, and the duration and intensity of outdoor activities. The NEA advised the public to check one-hour PM2.5 concentration readings and a personal guide for immediate outdoor activities.