"Winters first mega storm coming from December 11th in North India, be prepared for snow, rain and fog. Road, rail and air will be affected," Skymet CEO, Jatin Singh tweeted.
Cold weather conditions could be beneficial for the late sown wheat crop, which is yet to planted in some parts of the country including Uttar Pradesh and Punjab.
The state-run India Meteorological Department (IMD) in its forecast, too, said that temperatures over North India and in other parts of the country might remain appreciably below normal during the same period.
The met department in its annual winter weather prediction released earlier this month said that winters this year could be colder than last year but warmer than the normal across the country.
During the period between December, 2017 and February, 2018, warmer than the normal maximum and minimum temperatures are likely across the country, the met said.
The season's average maximum temperature is likely to be warmer by a degree Celsius in Rajasthan, Haryana, Delhi, eastern and western Uttar Pradesh, Gujarat, central Maharashtra, Vidarbha, Marathwada, west and east Madhya Pradesh, Arunachal Pradesh, Assam, Meghalaya, Manipur and Mizoram.
The last winter season 2016-17 witnessed an anomaly of 1 degree Celsius, which was the fourth warmest recorded since 1901.