The visibility in Delhi marginally improved today even as most parts of North India continue to reel under chilling cold wave conditions.
The visibility at Delhi's Palam airport improved from 'zero' at 4.30 am today to 50 metres at 5 am and further improved to 150 metres at 6.30 am, officials said.
A cold wave is likely to prevail over Delhi, Punjab, Haryana, Chandigarh, Uttar Pradesh and Rajasthan and at isolated places over Himachal Pradesh, and Uttarakhand for the next couple of days, the India Meteorological Department (IMD) said.
The early morning foggy weather in Delhi and adjoining areas has impacted road, rail, and air traffic over the past several days.
Several trains have been delayed today as well in parts of North India due to fog. Fliers have been asked to stay updated about the flight details since delays are usual on foggy mornings.
People have been taking refuge in government-run shelter homes to shield themselves from the freezing weather.
According to the weather office, "very dense" fog is when visibility is between 0 and 50 metres, while 51 and 200 metres is 'dense'.
A cold wave is declared in the plains when the minimum temperature dips to 4 degrees Celsius or falls 4.5 degrees Celsius below normal to 10 degrees Celsius or below.
Last Friday saw the season's first cold wave day with the temperature dipping to 3.9 degrees Celsius in Delhi. Saturday's was coldest night as the temperature fell to season's coldest at 3 degrees in Aya Nagar, the last village of Delhi on the Mehrauli-Gurgaon Road.
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