At 400 Delhi’s air quality index continues to be in the 'very poor' category

New Delhi: Mercury rose by a few notches in the national capital on Tuesday as the minimum temperature settled at 15.4 degrees Celsius, even as the air quality index remained in the 'very poor' category for the second consecutive day.The relative humidity in the morning was recorded at 85 percent, according to the India Meteorological Department.The maximum temperature is likely to settle around 28 degrees Celsius on Tuesday, it said. The minimum temperature on Monday had settled at 13.6 degrees Celsius, while the maximum was recorded 29.2 degrees Celsius.On Tuesday, the minimum temperature stood at 15.4 degrees Celsius, an IMD official said.The air quality index (AQI) of Delhi was recorded in the 'very poor' category at 400 in the morning, data from CPCB showed.It was in the same category on Monday as well, which was a marginal improvement from the last three days when it was recorded in the 'severe' category.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, and 401 and 500 severe.The weather department has forecast north-northwesterly winds later in the day.