Another cold day expected as air quality remains very poor in Delhi

A continuing thick layer of upper-level fog across the northern plains was expected to prevent sunlight from reaching the surface and lead to another cold day on Tuesday, the India Meteorological Department (IMD) said even as the air quality remained very poor. 
Delhi was expected to record a maximum temperature of around 17°C, the same as on Monday, or two degrees below normal. The season’s lowest maximum temperature of 15.9°C was recorded on Sunday. Delhi’s minimum temperature of 8.3°C on Tuesday was a degree above normal.
IMD scientist Kuldeep Srivastava said the shallow fog at the surface level reduced visibility to 500 metres at some places. “…dense fog persists at the upper levels of the atmosphere… [it] will prevent sunlight from reaching the surface even during daytime,” he said.
At least 26 trains to and from Delhi were delayed by over one hour on Tuesday morning even as no flights were impacted. Delhi recorded an average AQI of 343 (very poor) at 9am on Tuesday compared to 346 (very poor) at 4pm on Monday.
On Monday, the Commission for Air Quality Management (CAQM) in NCR lifted stage-3 or severe category measures under the Graded Response Action Plan (GRAP), citing a gradual improvement in air quality over three days. CAQM said the measures were disruptive as it lifted the ban on petrol BS-3 and diesel BS-4 four-wheelers and private construction.