Mumbai recorded 13 days in 'Good' air quality category (AQI below 50) and the remaining days in 'Satisfactory' category (AQI below 100) in July, according to Central Pollution Control Board (CPCB) data. Experts said heavy rainfall and strong winds helped clear pollutants and improve air quality. The city also recorded 10 'Good' AQI days in June and 12 in May.