Purulia in West Bengal witnessed an unusual winter spectacle as frost appeared across parts of the district amid record low temperatures over the past few days, officials said.

Frost covered farmlands and vegetation, and was seen on grassy fields, haystacks, bamboo poles, iron pipes and even four-wheelers, prompting comparisons with colder hill regions such as Sikkim and Darjeeling.

Officials explained that what occurred in Purulia was “ground frost”, a phenomenon in which ice crystals form directly on surfaces under favourable atmospheric conditions.

“Similar conditions were last recorded in the Begunkodor area of the district six years ago, on December 28, 2019,” an official said.“This season, the phenomenon resurfaced Wednesday onwards, coinciding with record-breaking cold,” he added.

According to the India Meteorological Department (IMD), Purulia recorded a minimum temperature of 4 degrees Celsius last week — an all-time low for the district and close to Darjeeling’s winter readings. Till Saturday, the mercury hovered around the 4-degree mark, while Darjeeling remained in the 3-degree bracket. On Sunday, Purulia recorded 5 degrees Celsius, compared to Darjeeling’s 3.6.

The district has consistently recorded lower temperatures than Kalimpong and Gangtok during this cold spell.

“On Sunday morning, frost covered grass in the Sitakund area of Ayodhya hilltop, while a nearby resort vehicle was seen draped in a white layer,” the official said.“Frost sightings were reported from Bandoan's Danga village, the Satymela area on the Jhalda-Khamar Road, and Supurdi village in the Begunkodor panchayat along the Murguma route,” he added.

The rare sight left both locals and tourists amazed.

“We are enjoying the cold. Haystacks are completely covered with ice. We didn't expect to see frost right here in Purulia,” said Monalisa Mahato, a local resident.

Experts, however, cautioned against confusing frost with snowfall. Dhruvajyoti Chattopadhyay of the Purulia District Science Centre said the phenomenon was purely frost deposition.

“This is frost deposition. When temperatures stay above zero but below 5 degrees, frost can form anywhere, not just in Purulia. Clear skies, pollution-free air and still wind conditions are essential, all of which have prevailed here for several days,” he told PTI.

Geography teacher Sanjay Kumar Mishra of Arsha New Integrated Government School explained that frost forms when the dew point drops below zero degrees Celsius, causing water vapour to turn directly into ice crystals instead of liquid droplets.

Somnath Mahapatra, an agriculture technology assistant responsible for temperature monitoring, said, “Purulia’s winter this year has shattered all past records. The minimum temperature has never dropped to 4 degrees C before.”