Safdarjung observatory

An AQI between 0-50 is marked good, 51-100 is satisfactory, 101- 200 is moderate, 201- 300 is poor, 301-400 is very poor and 401-500 is considered severe. 

In 1991, 1993, 1994, and 2007, the October MMTs were recorded at 17.6, 17.8, 17.9 and 17.5 degrees Celsius respectively, according to the IMD.