The overall Air Quality Index in Delhi was recorded in the ‘moderate’ category at 9 a.m. on Wednesday and the minimum temperature settled at 17.3 degrees Celsius, a notch below normal, officials said. The city witnessed poor air quality on Sunday and Monday. It improved slightly afterwards as gusty winds accompanied by rains lashed parts of the national capital on Monday night. The India Metrological Department predicted clear skies over the city during the day with no possibility of rainfall. It said the relative humidity was recorded at 82 per cent. An AQI between 0-50 is considered ‘good’, 51-100 ‘satisfactory’, 101-200 ‘moderate’, 201-300 ‘poor’, 301-400 ‘very poor’ and 401-500 ‘severe’. An AQI above 500 falls in the ‘severe-plus’ category.