Temperature to fall in the coming days, pollution expected to rise in Delhi
Forecasters said while the Capital has not shown any “abnormal” winter onset patterns till now, with the lowest temperature for the month falling to only around 16 degrees Celsius on October 21, the winter months ahead are likely to be frigid than usual
It is going to get colder in the city as cold winds blowing into Delhi from states that have recently reported snowfall, India Meteorological Department scientists said, adding that the minimum temperature may reach 14 degrees by the end of this month, normal for this time of the season.
On Monday, the maximum temperature recorded at the Safdarjung observatory, which provides representative data for the entire city, was 28.4 degrees Celsius, three degrees below what is considered normal for this time of the year. The minimum temperature was 16.4 degrees Celsius.
At the Palam weather station, the maximum temperature was 28 degrees Celsius, and the minimum was recorded at 18.2 degrees Celsius.
“Delhi has started receiving north-westerly winds from parts of Jammu and Kashmir, Himachal Pradesh and Uttarakhand that have recently reported snowfall. Cold winds from these states will blow into Delhi, bringing the temperatures down in the coming days. By October 30, the minimum temperature is expected to fall to around 14 degrees Celsius,” said a senior Met official.
Forecasters said while the Capital has not shown any “abnormal” winter onset patterns till now, with the lowest temperature for the month falling to only around 16 degrees Celsius on October 21, the winter months ahead are likely to be frigid than usual. They said under the impact of La Nina—a weather phenomenon that is marked by harsher winters and delayed withdrawal of monsoon—may result in lower than normal temperatures in north India this season, including in Delhi.
“While there is no major data to support how La Nina would impact winter in Delhi, but this weather phenomenon usually results in harsher winters with temperatures being recorded at slightly lower levels than normal. But it is difficult to predict precisely at his point. The October temperature trends so far have indicated a normal winters,” said Mahesh Palawat, vice-president (meteorology and climate change) at the Skymet Weather Services.
Palawat added, “Around the second week of November, temperatures are expected to start falling and we can officially call the onset of winter if around that time we get two to three intense western disturbances.”
Low temperatures, however, may also worsen the air quality as colder winds trap pollutants close the surface, and do not help proper dispersal.
However, a day after rain and hail hit parts of the national capital, the air quality in the city improved to the satisfactory zone on Monday, Central Pollution Control Board (CPCB) data showed.
According to CPCB data, the overall air quality index (AQI) on Monday was 82, categorised as ‘satisfactory’. This was a major improvement from Sunday’s 160, which was in the ‘moderate’ zone according to the AQI scale.
Union ministry of earth science’ air quality monitoring centre, System of Air Quality and Weather Forecasting And Research (Safar), said while the recent western disturbance that changed the direction of winds blowing into Delhi from the northwest, bringing stubble fire smoke from Punjab and Haryana, to easterlies, the pollution from farm fires will start coming to Delhi again this week.
On Monday, Safar’s satellite monitoring spotted 127 farm fires that contributed to around 6% of the city’s PM 2.5 levels (particulate matter with a diameter less than 2.5 micrometres).
“Around October 27 and October 28, the AQI is likely to fall to the higher end of ‘poor’ or the initial end of ‘very poor’ category,” the Safar air quality forecast said.