Fog eases in Delhi as max mercury hits season-low of 21.1°C

The smog eased in Delhi on Wednesday, after impairing commutes, flight and train operations for two straight days, with weather conditions helping to improve visibility early in the morning, even as the maximum temperature plunged to its lowest this season.

Delhi recorded shallow to moderate smog on Wednesday morning, with visibility at its lowest on the day significantly better than it was on Tuesday, when a thick haze blanketed the streets and skies.

The city clocked a minimum temperature of 7.1°C on Wednesday, a degree below normal, and a maximum of 21.1°C, also a degree below normal, and the lowest yet this season.

The lowest visibility in Delhi on Wednesday was in Palam, at 350 metres between 1am and 2am, followed by Safdarjung, at 500m, around 5.30am. In comparison, at its worst, the visibility on Tuesday was 25m at Palam and 50m at Safdarjung, both around 4.30am.

“Conditions have not changed much in the last 24 hours and wind speed continues to remain low. But Delhi had cloudy skies during the day on Tuesday, which generally makes it difficult for fog to form, since the heat does not escape quickly at night,” said RK Jenamani, scientist at the India Meteorological Department (IMD).

However, the rest of the Indo-Gangetic plains, including much of Punjab, Haryana, northwest Rajasthan, eastern Uttar Pradesh and Bihar were shrouded in a “dense to very dense” fog, said IMD officials.

Despite the fog, Delhi’s air quality improved slightly, dropping down to the lower end of the ‘very poor’ category, owing to an increase in wind speed during the day. Delhi recorded an overall AQI of 328 (very poor) as per Central Pollution Control Board’s national bulletin released at 4 pm. It was 366 (very poor) in comparison on Tuesday.