Update at 6pm

The Air Pollutant Index (API) throughout the country has generally eased by evening today as rain is reported in several areas in the southern areas of the peninsula.

The Malaysian Meteorological Department had issued a warning of heavy rains and thunderstorms across Johor including Johor Baru, Kulaijaya, Pontian and Batu Pahat.

It added that this is expected to persist until later tonight, with the likelihood of strong winds.

Reports of rain have also been reported in Klang, Rawang, Puchong, Serdang, Subang Jaya and several other areas across the Klang Valley.

Seri Manjung, Perak where the API reading exceeded the hazardous level at 328, has since eased to the ‘very unhealthy’ level at 276.

Shah Alam, which also breached the hazardous level at 9am with an API reading of 301, has also eased to 241.

However, Port Klang’s poor air quality remained hazardous with little change, recording an API of 461 as of 6pm today.

Update at 1pm

After Port Klang, the Air Pollutant Index (API) readings in Shah Alam and Seri Manjung, Perak hit hazardous levels this morning while the air quality is still "very unhealthy" all over the Klang Valley.

azlanThe API reading in Shah Alam broke the 300 mark to 301 at 9am but dropped slightly to 291 at 11am, while API reading in Seri Manjung degraded to 333 at 11am.

Port Klang continued to be hazardous with an API reading of 484 at 11am, the highest nationwide.

The Department of Environment (DOE) reported at 11am that the air quality in other areas of Selangor - Banting (266), Kuala Selangor (229) – still categorised as 'very unhealthy', while Petaling Jaya is at an ‘unhealthy’ 199.

Except Seri Manjung, API readings in Perak, Kuala Lumpur, Putrajaya, Negri Sembilan, Malacca and Penang are generally within the 'unhealthy' level, ranging from 117 to 198.

The haze in Johor has subsided with only Muar exceeding the 100 mark at 132.

In his Facebook page, Natural Resources and Environment Minister G Palanivel stated that cabinet has instructed for an hourly record of the API readings from today.

Previously, readings were recorded at 7am, 11am and 5pm on the Department of Environment's (DOE) website.

Update at 8.30am

The Air Pollutant Index (API) in Port Klang hit hazardous level this morning with a reading of 487, while the air quality is "very unhealthy" all over the Klang Valley.

The API reading in Port Klang has worsened significantly after it breached 314 at 3pm yesterday.

azlanThe Department of Environment (DOE) reported at 7am that the air quality in Selangor - Banting (292), Shah Alam (289), Kuala Selangor (242) and Petaling Jaya (213) - has also degraded.

Perak also saw an API reading breaching the 300 mark, with Seri Manjung showing 288.

According to the API, a reading of 0-5 denotes good air quality; 51-100 (moderate); 101-200 (unhealthy); 201-300 (very unhealthy); above 301 (hazardous to human health).

The trans-boundary air pollution is blamed on land-clearing activities in Sumatra.

DOE Air Pollutant Index - check API readings nationwide

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