As mercury dips in Delhi, air quality set to worsen this week

After a brief respite over the last week, mercury has started to dip again in the capital and is forecast to dip further
until Thursday, as per scientists at the India Meteorological Department (IMD).

Cold winds blowing from the northwest brought the minimum temperature down to 3.7 degrees Celsius in Southwest Delhi’s Jafarpur on Tuesday, as per the IMD. The department’s Safdarjung observatory, which is representative of the city, recorded a minimum temperature of 4.3 degrees Celsius — three degrees below normal for this time of the year.

Kuldeep Srivastava, head of IMD’s regional weather forecasting centre, said, “Due to a Western Disturbance, there was snowfall over the last week in the mountains in northwest India. The wind direction has now changed over Delhi and cold winds are blowing from the areas where snowfall was recorded.”

Mercury has been steadily dipping in the early morning hours since January 7 when it was 14.4 degrees Celsius. A Western Disturbance also brought showers to Delhi last week and the city has recorded 56.6 mm of rainfall so far this month.

The average normal rainfall Delhi receives in January is 19.3 mm, as per IMD data. No rainfall is forecast for the next seven days, Srivastava said, but minimum temperature may fall further by one or two degrees on Wednesday.

Maximum or day time temperature had dipped to 16.2 degrees Celsius on Sunday, from 22.6 degrees on January 5. It was 17.6 degrees Celsius on Tuesday.

The temperature is expected to stabilise after Thursday, Srivastava said. It is forecast that the minimum temperature would be 4-5 degrees Celsius until January 18 and maximum would be 18-19 degrees Celsius.

Meanwhile, Delhi’s air quality index (AQI) deteriorated within the poor category on Tuesday and was recorded as 293, higher than 243 on Monday.

The Ministry of Earth Sciences’ air quality monitor SAFAR has forecast that the AQI would slip into very poor category by Thursday.

“AQI is likely to further deteriorate on January 15 to the higher end of the very poor category due to calm winds and extremely low ventilation condition,” a bulletin from SAFAR said.