Eleven flights arriving at and departing from Chandigarh airport were cancelled on Friday because of poor visibility, ANI reported. The airport suspended all flight operations on Thursday after a dust storm. Various parts of North India have faced sandstorms in recent days and a thick dusty haze has enveloped Delhi and nearby towns since Tuesday.

The air quality in Delhi and the National Capital Region remained hazardous even after a slight improvement on Thursday evening. The situation had deteriorated earlier because of incoming dust from Rajasthan, the Ministry of Environment said.

The concentration of pollutant PM 10 – particulate matter with sizes lower than 10 microns – was at 759 micrograms per cubic metre at 4 pm on Thursday, against a high of 823 micrograms per cubic metre the previous evening, the government said. The level was 744.4 micrograms per cubic metre at noon on Friday.

The level of PM 10 has stayed over the dangerous 500 micrograms per cubic metre for the last 60 hours, according to the Central Pollution Control Board.

Union Environment Minister Harsh Vardhan directed agencies to be “on maximum alert” and take necessary measures to contain the sources of dust and check the burning of garbage. He also asked people to “avoid unnecessary exposure”.

In its morning update on Friday, the India Meteorological Department forecast thunderstorms with gusty winds and lightning for Delhi, Haryana, Chandigarh and Punjab till Tuesday. Parts of Western Uttar Pradesh are likely to have dust storms or thunderstorms till Saturday, the weather department said.

On Thursday, Delhi Lieutenant Governor Anil Baijal ordered all civil construction activities across the Capital to be stopped till Sunday as part of emergency measures to reduce severe dust pollution.

The minimum temperature in Delhi was recorded at 33.4 degrees Celsius on Friday, six degrees above normal, PTI reported.

India Meteorological Department Regional Director S Paul told ANI that there is a thick blanket of dust over Chandigarh city. “As of now, it seems that there will be some respite from these conditions in the next 48 to 72 hours,” he said. “Monsoon is still in weak phase, however, there are chances of its revival by the end of the month.”