Dense fog gripped Delhi-NCR with visibility dropping to zero at most places.
The IMD said that minimum temperatures are likely to fall by 2-4 °C over parts of northwest India.
Flight services from Delhi were hit due to heavy fog enveloping the city-state.
Meanwhile, air quality remained in 'severe' category in several parts of Delhi-NCR.
Air quality index (AQI) of the national capital on Saturday morning was 441.
Faridabad, Ghaziabad, Greater Noida and Noida also recorded 'severe' air quality.
This happens mainly due to low wind speed not allowing dispersal of pollutants in the air.
Dense fog at isolated pockets is likely over many north Indian states during the next three days.
Cold wave conditions are also likely to prevail over the northern states during the next two days.
