New Delhi, Jan 10 (IANS): Continuous rains since Friday night have brought Delhi's Air Quality Index (AQI) to a "good" category of 77, System of Air Quality and Weather Forecasting And Research's (SAFAR) showed Monday morning.

The level of both PM 2.5 and PM 10 pollutants at 10 a. m. stood in the "good" category of 46 and 63, respectively.

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

According to the air quality and weather bulletin, the air quality over Delhi-NCT is likely to deteriorate marginally but remain in the "moderate to poor category" on January 11. The winds are likely to be relatively slow and thereby low ventilation causing the air quality to deteriorate.

The air quality is likely to remain in the "poor" category on January 12. "The predominant surface wind is likely to remain calm during morning/day time but likely to be coming from the northwest direction of Delhi with wind speed upto 04 kmph during evening/night, mainly clear sky and moderate fog in the morning on January 11. The predominant surface wind is likely to be coming from the northwest direction of Delhi with wind speed upto 04 kmph, mainly clear sky and moderate fog in the morning on January 12," it added.

The air quality is likely to remain largely in the "poor" to the lower end of the "very poor" category for the five subsequent days.