Intense cold wave gripped the lower hills of Himachal Pradesh as the local weather department issued an orange alert for severe cold in Bilaspur, Una, Hamirpur and Mandi districts for four days from Monday.

The meteorological department also predicted light rain and snowfall at a few places in the mid and higher hills till Thursday.

While the minimum temperatures stayed below normal, the weather remained dry and day temperatures dropped by two to three degrees.

Tabo was coldest in the state with a low of minus 11. 6 degrees, while Sumdo, Kusumseri and Kalpa recorded a low of minus 5.3 degrees, minus 4.8 degrees and minus 1.8 degrees Celsius, respectively.

Una recorded a low of 1.0 degree, followed by Bhuntar 1.5 degree Celsius. Una was also the hottest place in the state with a high of 23.8 degrees, down from Saturday's 24.5 degrees Celsius.

The weather station also issued a yellow warning of dense fog over some parts of Bhakra Dam reservoir area and Balh Valley in Mandi from December 24-26. Thick ground frost could be seen at isolated places in the lower hills from December 24-26.

An active western disturbance is likely to affect the western Himalayan region and adjoining plains from December 27 onwards. Light rain and snow are likely at isolated places over the state on December 23 and 24 and at many places on December 27 and 28, causing a gradual fall in temperatures.

The high-altitude tribal areas and mountain passes reeled under piercing cold wave conditions, with the mercury staying 14-18 degrees below freezing point. Water pipes were frozen at many places in mid and higher hills, and the natural sources of water like springs, rivulets and tributaries of snow-fed rivers were frozen, reducing the discharge of water, which severely affected hydropower generation.

Farmers in the state are a worried lot due to the continued dry weather and presence of frost, which was injurious for Rabi crops sown in November and December.