The yearly haze that returned with a vengeance yesterday appears to be worsening, with the number of areas hitting ‘unhealthy’ levels climbing this morning.

According to the Department of Environment website monitoring the situation, the number of areas hitting the 101-200 air pollutant index (API) level had increased between 7am and 11am.

NONE The readings remain stable in most places by 5pm.

Readings for Port Klang continue to drop from 144 at 7am to 142 at 11am, and to 140 at 5pm, while the air quality in Cheras improved from 133 at 11am to 130 in 5pm.

Despite improvements, the API levels there still indicate unhealthy levels, alongside other areas in the Klang Valley like Petaling Jaya (130) and Kuala Lumpur (Batu Muda, 127) which chalk among the highest readings.

The other badly hit areas are Kuala Selangor , Banting and Nilai (Negri Sembilan) - all just exceeding 100.

The air quality in Putrajaya improved slightly, dropping from 101 at 11am to 98 as of 5pm.  

Forest fires in Sumatra blamed

Overall, the smog, blamed on forest fires in neighbouring Indonesia, has affected 80 percent of the country, in particular West Malaysia, with the east coast of Sabah and Sarawak being moderately affected.

The readings today suggest that the situation has deteriorated since the reports yesterday.

Haze is an annual problem during the monsoon season from May to September as winds blow the fumes from Sumatra across the Straits of Malacca to Malaysia .

Skies over Kuala Lumpur today were gloomy and visibility was described as poor by the Meteorological Department.

With dry weather forecast for the next week, air quality is expected to deteriorate further.

Indonesia's government has outlawed land-clearing by fire but weak law enforcement means the ban is largely ignored.