Mercury drops in Delhi after snowfall in hills

The air quality of Delhi also dipped drastically during the day. After remaining in the poor zone for two days, the Air Quality Index (AQI) value shot up to the ‘very poor’ on Wednesday.

Near-cold wave conditions gripped the national capital as the mercury dropped to 4.5 degrees Celsius in the early hours of Wednesday. According to the India Meteorological Department (IMD), the temperature could drop to 4 degrees Celsius in parts of the city early Thursday as northwesterly winds are bringing in the chill from the hilly regions of Himachal Pradesh and Jammu and Kashmir, which have received fresh snowfall.

A woman walks across an open field enveloped in dense fog on a cold winter morning, near Akshardham, in New Delhi on January 16. (Biplov Bhuyan/HT PHOTO)

A cold wave, as defined by IMD, is a weather condition in which the minimum temperature drops below 4 degrees Celsius.

It was on New Year’s Day that the night temperature last dropped to 4 degrees Celsius. The lowest temperature since was the 4.8 degrees Celsius on January 11.

The city’s air quality also dipped on Wednesday. After remaining in the “poor” zone for two days, the Air Quality Index (AQI) value was at the “very poor” level on Wednesday.

While Wednesday’s minimum temperature was three degrees below normal, the maximum temperature was 21.3 degrees Celsius, one degree above normal.

IMD forecast that the temperature in the remaining part of this winter would be above normal in the city, which experienced the coldest December in 13 years. Although January is typically the coldest month of the year, the first 15 days have been warmer than the last 15 days of December. “A western disturbance has triggered snowfall in the hilly areas of Jammu and Kashmir and Himachal Pradesh. The northwesterly winds are bringing in the chill from those areas,” said Kuldeep Srivastava, head of the regional weather forecasting centre in New Delhi.

IMD has also forecast light to very light rain on January 22. It said that another western disturbance is approaching, which could trigger rain early next week. “As the disturbance approaches, the night temperature is expected to rise. It could touch 10 degree Celsius by Monday,” said Srivastava.

The AQI reading on Wednesday was 371 after the index remained in the “poor” zone, with values between 201 and 300, over the last two days. “Strong winds had helped to clean up Delhi’s air since Monday. On Monday, the wind speed had shot up to 20km/hour which is usual for this time of the year. But now that the wind speed has dropped below 10 km/hour, the pollution is picking up,” said an official of the Central Pollution Control Board. Strong winds help carry pollutants beyond the city’s borders. Pollutants accumulate in the city when the wind speeds drop.