Air quality in the national capital deteriorated to ‘very poor’ category on Thursday.

Dust blowing over the north western region in the country was the major factor for the deterioration in the air quality, said Safar, the central government’s air quality forecasting agency.

The air quality index (AQI) was recorded as 347 with the prominent pollutant being PM 10, which is mainly dust.

An AQI between 0 and 50 is considered ‘good’, 51 and 100 ‘satisfactory’, 101 and 200 ‘moderate’, 201 and 300 ‘poor’, 301 and 400 ‘very poor’, and 401 and 500 ‘severe’.

The air quality is expected to get better with the possibility of thunderstorm and gusty winds hitting the city on Friday evening, said a statement released by Safar.

“Air quality in the city is expected to remain at the upper end of the very poor category till Friday afternoon. However, thunderstorm and gusty winds triggered by an approaching Western Disturbance are expected to clear the air as well as bring the mercury down,” the statement said.

Delhi has been witnessing hot and dry days with the maximum temperature soaring to 43.7 degrees Celsius on April 30.

The maximum temperature on Friday was recorded as 41.8 degrees Celsius, three notches above normal.

The minium settled at 26.4 degrees C, two notches above normal.

First Published: May 10, 2019 04:30 IST