The air quality index in Delhi and NCR regions such as Noida and Gurugram have reached the "severe plus" category, prompting the implementation of pollution-curbing restrictions and GRAP IV in Delhi.

The AQI in Delhi-NCR is in the ‘severe plus’ category. AQI between 0-50 is considered “good”, 51-100 is “satisfactory”, 101-200 is “moderate”, 201-300 is “poor”, 301-400 is “very poor”, 401-500 is “severe” and above 500 is a “severe plus”.

According to reports, more than 20 trains were delayed and at least eight flights diverted due to low visibility.