Showers expected on Thursday, but slight haze likely to persist

The haze situation in Toa Payoh at around 9am on Oct 28, 2015. ST PHOTO: LEE MIN KOK

SINGAPORE - Haze and visibility conditions in Singapore have improved dramatically, after early morning showers over most parts of the island brought much needed reprieve on Wednesday (Oct 28).

Thundery showers are forecast for Wednesday night as well, and again in the pre-dawn hours and early morning on Thursday. However, occasional slightly hazy conditions can still be expected and visibility could be slightly reduced if PM2.5 concentration levels are elevated, the National Environment Agency (NEA) said in an update on Wednesday evening.

PM2.5 refers to toxic particles that are 2.5 microns or smaller, which are usually emitted by forest fires, vehicles and power plants, among others.

"The air quality for the next 24 hours is expected to be in the high end of the moderate range, and may enter the low end of the unhealthy range if winds are unfavourable," it said of the conditions expected on Thursday.

On Wednesday, air pollution levels fell into the moderate (51-100) range in the afternoon.

As of 6pm, the 24-hour Pollutant Standards Index (PSI) was 80-93. The three-hour PSI, which is not tied to a health advisory, stood at 97.

The total number of hotspots detected in Sumatra and Kalimantan on Wednesday was 62 and nine respectively.

"There has been an increase in shower activities in the region and a reduction in the extent of the haze over Sumatra and Kalimantan has been observed. However, some haze is still observed over the surrounding sea areas to the southeast of Singapore," NEA said.

Earlier in its 8am update on Wednesday, the NEA said current conditions are expected to persist for the rest of Wednesday in Singapore.

Prevailing winds are forecast to continue blowing from the east, with the 24-hour PSI for the next 12 hours staying between the moderate and low end of the unhealthy range.

Indonesian vice-president Jusuf Kalla said on Tuesday that the government might officially declare the current haze crisis, which has shrouded parts of the region in thick smoke since August, a national emergency.

The haze situation had prompted President Joko Widodo to cut short his first official visit to the United States by a day.

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

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