Shallow fog was recorded at some places in the city. (File)New Delhi: Delhi’s minimum temperature increased marginally on Wednesday due to partly cloudy sky and settled at 8.2 degrees Celsius, a notch above normal.Shallow fog was recorded at some places in the city.According to the India Meteorological Department (IMD), the national capital recorded a maximum temperature of 18.1 degrees Celsius, two notches below normal.Over the last three days, Delhi has seen a sharp decline in the minimum temperature due to cold northwesterly winds which commenced after the withdrawal of a western disturbance.The minimum temperature had increased up to 15.2 degrees Celsius on January 8 due to cloudy weather last week. It came down to 6.5 degrees Celsius by Tuesday.Clouds trap some of the outgoing infrared radiation and radiate it back downward, warming the ground.