Delhi, the capital city of India, has an ill repute of a polluted city specifically due to high ambient particulate concentration resulting Hazy conditions. Winter of 2012 in Delhi was characterized with high level of critical pollutants, which in general, were attributed to geographical location of the city, high vehicular and population density. The onset of winter 2012 witnessed hazy and dusty condition, which prevailed for about 20 days (October to November), which is uncommon for this period of the year. No changes in the pattern of polluting activities in Delhi city were observed, which further compelled Delhi Pollution Control Committee to find out the associated reasons. The activities in neighboring states like agricultural waste burning in Punjab and Haryana and development of cyclone on coast of Tamil Nadu during this period might be one of the factored reasons for the hazy conditions.