The TMD forecasts that stagnant air, which allows PM2.5 haze to accumulate, will hang over the metropolitan area until Friday (March 10).
On Saturday and Sunday, southeasterly winds of up to 25 km/hr will blow in to improve air circulation and reduce PM2.5 levels, said the department.
On Thursday morning, data from the city’s air-quality monitoring stations across 70 areas showed PM2.5 levels ranging from 56 to 96 micrograms per cubic metre (mcg) of air.
Any level above 50mcg is considered unsafe as long-term exposure is linked with chronic diseases including lung and heart problems.
City officials have advised residents to wear face masks and avoid outdoor activities. Those who have difficulty breathing, eye inflammation, chest pain, or headaches after going outside should see a doctor.