Experts blame lack of strong western disturbances for fog

Dense fog and low clouds over the Himalayan foothills and the entire Gangetic plains till the Bay of Bengal that has persisted for a week to Tuesday is because of high moisture content in the upper atmosphere and lack of strong western disturbances, compounded by heavy particulate pollution and cold day temperatures, meteorologists said.

- Jayashree Nandi

There has been an unusually low number of active western disturbances this winter, which is also resulting in extremely dry conditions over upper reaches of western Himalayas that are normally covered by snow during this time of the year, they said.

The movement of active western disturbances has shifted north, giving the Indian landmass a miss so far this winter, officials said. However, mild western disturbances that leave moisture behind are continuing to impact the region. On Tuesday, Delhi, Gurugram, Faridabad, Chandigarh, Bhiwadi, Bahadurgarh, Ghaziabad and Greater Noida, among others, also recorded very poor air quality, according to Central Pollution Control Board data.