New Delhi, National Capital’s air quality deteriorated on Tuesday morning with the average Air Quality Index measuring at 346 at 0900 hrs, the Central Pollution Control Board said.The AQI at several areas in Delhi was above 350 , while at a couple of places it was almost touching 400 and at Ashol Vihar it was above 400, where the air quality was under ‘severe’ category.Cities in the NCR like Ghaziabad, Gurugram, Noida, Faridabad also reeled under ‘very poor’ air , as per the CPCB data.Two of the Ghaziabad’s monitoring stations measured AQI above 400 , where the air quality was under severe category.According to IMD minimum temperature recorded on Tuesday morning in Delhi was 7.6 degrees C , while relative humidity was on the higher side pegging at 95 per cent this morning, both the factors contributing in making the air dense, which further prevents dispersion of the particulate matter amid slow wind speed.The weatherman has forecast mist during Wednesday morning , while minimum temperature tomorrow is likely to hover around 8 degrees C.