Dense fog, low visibility hit Delhi again; morning temperature dips to 4.2°C

Saturday will have moderate fog and temperature will be same as that on Friday. Sunday could see shallow fog, with the maximum temperature dipping by a notch at 19°C.

Delhi woke up to a foggy morning on Saturday, with minimum temperature dipping to 4.2°C — lowest of the season so far. Disruptions in train operations continued.

Fog at India Gate in New Delhi early Saturday morning. (ANI Twitter)

Over 49 trains were running late, 13 rescheduled and 18 cancelled due to low visibility in Delhi on Saturday morning, railway officials said.

Delhi International Airport Limited officials, however, said there was no disruption in flight movements in the early hours due to fog.

According to the Met department, Saturday will have moderate fog and temperature will be same as that on Friday. Sunday could see shallow fog, with the maximum temperature dipping by a notch at 19°C.

On Friday, at the Safdarjung observatory, which is considered a representative of the entire city, visibility was down to 300m till 7.30am.

“During the day it (the visibility) improved to 1,500 metres. This is because of good wind speed to the tune of 8-10km/hour. Later, in the afternoon, it went back down to 700 metres,” Kuldeep Srivastava, a senior Met department scientist, said.

The minimum dropped to 5°C on Thursday — the lowest in January so far this year. The dense fog resulted in pollutants getting trapped in the air.

Pollution-wise, Delhi’s average Air Quality Index (AQI) reached 398 on Saturday morning. This was slightly more than Friday’s 388 and marginally more than Thursday’s 362, all in “very poor” level. The AQI is calculated on a scale of 0-500. An AQI between 0-50 is considered good, 51-100 satisfactory, 101-200 moderate, 201-300 poor, 301-400 very poor and 401-500 severe.

According to the CPCB real-time monitoring, at 8am on Saturday, the concentrations of PM2.5 and PM10 were 261.3ug/m3 and 411.5ug/m3 respectively. The particulate matters kept fluctuating as on Friday at 6pm the concentrations of PM2.5 and PM10 were 236.2ug/m3 and 354.1ug/m3.

Both PM10 and PM2.5 are ultrafine particles, the dominant pollutants in Delhi. The acceptable levels of PM10, the larger particulate matter, and PM 2.5, which measures the finer and more dangerous particulate matter, are 100μg/m3 and 60μg/m3, respectively.