A blanket of smog descended on the city in the early hours of Wednesday.
Smog reduced visibility to 1200 meters between 8.30 am and 10.am before lifting, the Met department said.
The below-normal visibility affected traffic, that crawled in the peak hours at several places especially Palam, Delhi-Gurgaon road and parts of East Delhi, the weatherman said.
“Due to low temperature, pollution condensed and formed smog. There was mist also. So visibility was hit,” said the duty officer at Safdarjung met office.
Thanks to rising level of vehicular emission, the smog — smoke and pollution combined — has become common in Delhi in the past few years.
Dust particles and harmful toxic gases like ground-level ozone, sulphur dioxide and carbon monoxide present in smog descend to levels that expose humans to these pollutants.
“In winter, the atmosphere loses its natural ability to ventilate itself. So people are at graver risk, especially those already suffering from cardio-pulmonary diseases,” said Anumita Roychowdhury, associate director, Centre for Science and Environment.
“The minimum temperacience on Wednesday was 15.6 degrees Celsius and the day temperature around 28.6 degrees Celsius,” said the weatherman.
Thursday temperatures will be similar with chances of mist and smog, he added.