Moderate fog cover was today witnessed in the national capital, leading to delay in 52 rail services and rescheduling of 12 others.<br/><br/>Flight operations at Indira Gandhi International Airport though were normal, airport officials said.<br/><br/>According to a Meterological department, visibility was recorded at 1500 metres at 5:30 A.M. Three hours later, it reduced to 400 metres.<br/><br/>The minimum temperature settled at 8.2 degrees Celsius. Relative humidity was recorded at 92 percent at 8:30 A.M.<br/><br/>The Meterological department predicted that the skies will be mainly clear as the day progresses.<br/>