Road and rail services were affected with traffic moving slowly.
Reports from various places said that visibility was reduced to 50-200 metres at different places.
Hisar and its surrounding areas in Haryana were engulfed in thick fog on Thursday morning with visibility reduced to 50 to 100 metres.
Traffic movement on the busy National HIghway (NH-1), which runs through Punjab and Haryana, connecting Amritsar with Delhi, was also affected due to fog.
Moderate to dense fog was reported from several parts of the national capital region (NCR) in Haryana comprising districts of Gurugram, Faridabad, Jhajjar, Hisar, Bhiwani, Sonipat, Panipat, Karnal and Rohtak.
Dense fog was reported from several areas of the NH-1 between Ambala and Kundli border of Haryana and Delhi.
A few trains were running behind schedule due to the fog.
In Punjab, fog was reported from Amritsar, Ludhiana and Jalandhar districts.
Met officials here said that foggy weather would prevail over the next few days.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)