Chill arrives in Chandigarh: Day temp drops 8.7°C in 2 weeks
In the two weeks between October 20 and November 3, the maximum temperature in Chandigarh had seen only a slight change, moving from 33.3°C to 32.8°C
While the declining air quality remained in focus since the beginning of November post Diwali, the mercury has also been dropping steadily, bringing a noticeable chill in the air.
In the two weeks between October 20 and November 3, the maximum temperature had seen only a slight change, moving from 33.3°C to 32.8°C.
However, in the following two weeks, the mercury has rapidly fallen to 24.1°C as of November 17 — a drop of 8.7 degrees.
In comparison, the minimum temperature, which was 18.4°C on October 20, was down to 15°C by November 3, and two weeks later, after some fluctuations, has slid further to 13°C, the lowest of the season till now.
Western Disturbance, smog behind temp change
Speaking about the sudden fall in temperature, IMD Chandigarh director Surender Paul said, “Because of the effect of the Western Disturbance, some snowfall was seen in parts of Kashmir. While the WD was too northwards to affect the rest of the region, it still brought about decline in temperature. Earlier, the temperatures had been higher than normal due to the effects of Cyclone Dana and lack of rainfall in the region.”
Further, Northwesterly winds have also started blowing in the region. While these winds helped bring respite from the prevailing pollution, helping the Air Quality Index (AQI) drop from “very poor” to “poor”, they have also led to drop in temperature due to their cool nature, he added.
The smog recorded earlier this week is also to blame for cooler days, as per Paul. He explained that even the presence of pollutants in the air makes temperature fall as they reflect any sunlight reaching the Earth’s surface.
More fog on the cards
Fog formation is likely to continue in the coming week as the WD combined with a low pressure area brought in a lot of moisture into the region from the Bay of Bengal. Even as AQI has gone down, humidity remains high and chances of dense fog will continue, even as it will not be like the haze witnessed last week due to smog.
On Sunday, visibility went down to just 80 metres at 8.30 am at the IMD Sector 39 observatory. It was at 100 metres at the airport at the same time, but improved to 3,000 metres in the afternoon. Paul said unless the wind speed got faster, fog formation was likely to persist.
Because of the fog, the maximum temperature fell from 26.6°C on Saturday to 24.1°C on Sunday, 2.1 degrees below normal. Over the next three days, the maximum temperature will remain between 24°C and 26°C, and the minimum temperature may drop further to 12°C.
AQI continues to remain poor
The AQI, meanwhile, continued to remain poor for the second day in a row, going up from 277 on Saturday to 287 on Sunday. While this is an improvement over last week when AQI had crossed 400 (severe), an AQI even between 201-300 can cause breathing discomfort to most people on prolonged exposure.
In the coming days, AQI is likely to remain around similar lines. Paul explained that Northwesterly winds will continue to disperse the pollutants. However, as mercury falls further, temperature inversion is expected to intensify, which can lead to increase in AQI, as cooler temperatures keep pollutants in the air from scattering.
