The Indian Meteorological Department (IMD) has predicted that ground frost will occur in the next two days in some places in the hills of Nilgiris, Coimbatore and Dindigul districts in Tamil Nadu.

Many places in Tamil Nadu have been facing a cold wave over the past few days, with the minimum temperatures in some places touching as low as 4 degree Celsius. Extensive frosting was also recorded in those areas over the past few days. While Ooty in Nilgiris and Valparai in Coimbatore recorded single-digit temperatures, Kodaikkanal in Dindigul district was also not far behind.

Weather bloggers have predicted similar cold temperature across Tamil Nadu in the coming week till Pongal. “Cold conditions to continue till Pongal. Hosur becomes colder than Ooty and Kodaikanal. Western & interior Tamil Nadu districts such as Tiruppur, Erode, Krishnagiri, Dharmapuri, Coimbatore, Vellore continue to shiver in cold temperature,” posted Pradeep John, a Chennai-based weather blogger who goes by the name Tamilnadu Weatherman on his Facebook page.

As on Saturday, Valparai recorded 3.5 degree Celsius and Kodaikkanal and Ooty recorded 7.3 and 7.4 degree Celsius respectively. Pradeep John attributed this cold wave to a dip in the jet stream above Tamil Nadu.

Jet streams are like strips of strong winds, which form a border between hot and cold weather. These winds influence the average temperature of the region over which it flows. “With Jet stream expected to dip again and then with High pressure expected to dominate the Indian peninsula, the cold days are expected to continue in interior Tamil Nadu. Bangalore, Mysuru too will be colder than normal,” he added.

On January 2, Valparai recorded a temperature of 3.5 degree Celsius and Ooty was at 4.4 degrees with frosting in both these locations.

The cold wave began in Tamil Nadu on January 1, as the northeast monsoon retreated from south India.