The death toll due to the current cold spell in northern India mounted to 29 Friday with four more deaths in Uttar Pradesh and one in Haryana while foggy conditions worsened, reducing visibility and disrupting rail traffic at a few places.

Two deaths were reported from Kushinagar and one each from Hamirpur and Mahoba in Uttar Pradesh. The intense cold also claimed  its first victim in Sonepat in Haryana, officials said.

The meteorological office said the mercury hovered 1 to 5 degrees below average, a slight rise from Thursday's 2-6 but the fog had thickened.

It predicted rain or snow at isolated places in Himachal Pradesh and ground frost in parts of Punjab and Haryana over the next 48 hours.

Reports said rail traffic was disrupted at a few places in Haryana owing to the foggy conditions.

A blanket of early morning fog enveloped Delhi and visibility was down to 500 metres even though the minimum temperature read markedly above Monday's low (3.3) at 5.3 degrees Celsius and maximum 21.9 (2 below normal).

Srinagar [Images] recorded minus 3.6 (2 below normal) while Jalandhar was 0.4, the coldest place in the plains. Kanpur was the coldest at 4 in Uttar Pradesh, which has accounted for a majority of the deaths since the onset of the cold wave.

In Punjab and Haryana, Amritsar [Images] recorded 1, Ludhiana 1.9, Ambala 2.4 while Karnal, Patiala and Chandigarh were at 4 C.

Bhuntar in Himachal Pradesh had a low of minus 0.2 and Sundar Nagar minus 0.9 C.