Polar vortex likely behind the increase in western disturbances , which is behind the cold weather in North India.



Many parts in the Himalayas have seen one of the heaviest snowfall episodes in the past few days.



More western disturbances expected until Mid-February.





A combination of prolonged western disturbances and polar vortex, a phenomenon that is pushing Arctic winds downwards, may be behind the unusually cold winter season in North India, say weather experts.Many parts in the Himalayas have seen one of the heaviest snowfall episodes in the past few years. Its effect is being felt across North India and even in the southern states of Maharashtra and Telangana, which have seen colder temperatures. Temperatures dipped below zero in some parts of Rajasthan, which is only the fourth time in the last decade that has been seen, said Mahesh Palawat, vice president of Meteorology and Climate Change at Skymet.“Until February, we expect more active western disturbances,” said Palawat, adding that will likely result in an extended winter in North India.India has already seen six instances of western disturbances so far, increasing both in frequency and intensity, noted Palawat.Western disturbances are caused due to winds travelling from West to East and usually travel in the “upper latitudes” over Kazakhstan and Russia. This year, these disturbances -- usually seen during winter months -- have been pushed south because of the polar vortex currently sweeping North America and Europe.A polar vortex is a narrow band of freezing air which rotates in an anti-clockwise direction during the winters on the North Pole. It can expand or break when it encounters a temperature difference, which pushes down icy winds towards North America and parts of Europe.This year, the pushing down of the polar vortex is in effect “transmitting the cold from Southern Europe to North India,” D Sivananda Pai, a senior official with India’s Meteorological Department (IMD) told Times of India. It is the first time since 2014 the world is seeing a polar vortex phenomenon, which many climate scientists say could be linked to global warming.“Snowfall is expected across the western Himalayan region— J&K, Himachal Pradesh and Uttarakhand and the Northern plains are likely to get rains with hail in some areas,” BP Yadav, an official of India’s Meteorological Department told Times of India.