SINGAPORE - The haze has abated for now, with better air quality continuing into Wednesday morning.
The three-hour Pollutant Standards Index (PSI) stands at 77 as of 8am, while the 24-hour PSI is in the range of 70 to 76.
Air quality started to improve on Tuesday morning and has remained in the moderate range since then. This was after the three-hour PSI hit the unhealthy level of 153 at 7pm on Monday - the highest recorded this year.
Singapore has experienced occasional bouts of haze over the last month following Sept 15, when the PSI level crossed into the unhealthy range for the first time since April.
At such levels, prolonged or strenuous outdoor physical exertion should be reduced or avoided. Normal activities can carry on at PSI readings of 100 and below.
The National Environment Agency said in its daily haze advisory on Tuesday that the improved condition was due to "a change in the prevailing wind direction, blowing from the south-east".
Prevailing winds on Tuesday are also forecast to be from the south or south-east, it noted.
Showers in the late morning and early afternoon are expected and the overall air quality should be mainly in the high end of the moderate range, but may move into the low end of the unhealthy range should the winds turn unfavourable.