A widespread rains wave on Friday night gave Delhi its wettest January in 22 years, just eight days after the start of the new year, data from the Indian Meteorological Department (IMD) showed, as downpours cleaned up pollution from the city, giving the capital an air quality index (AQI) below 100 for the first time since mid-October.
IMD’s Safdarjung Observatory, considered the city’s official weather marker, recorded 41mm of rain on Saturday. The last time Delhi saw more rain in January was in 1999, when the city recorded 46mm of precipitation on January 7.
The Palam weather station received 47.6mm of rain over the same period, which IMD says is the highest rainfall in 27 years. On January 9, 1995, the Palam station recorded 52.2 mm of precipitation.
Weather officials attributed the rain to a western disturbance and induced cyclonic circulation. The disturbance in the west affects northern Pakistan and neighboring areas, while the induced cyclonic circulation affects eastern Rajasthan and neighboring areas, IMD said in a press release on Saturday.
RK Jenamani, senior scientist, IMD, said that while the western disturbance is a routine occurrence, the widespread rain this time is due to a “strong” western disturbance.
“Some western disturbances are so strong that their tail is as far as the central part of the Arabian Sea. The weather activity we witnessed was due to a huge western disturbance that picked up moisture from a large area of the central Arabian Sea and covered areas such as Punjab, Haryana, Rajasthan , Madhya Pradesh, Delhi, Himachal Pradesh and Uttarakhand, ”Jenamani said.
He said Punjab, Haryana and parts of Rajasthan also experienced high rainfall. “The disturbance in the west has resulted in heavy rainfall in a number of areas. This does not normally happen. The western disruption was very active this time, ”he said.
The rain brought down temperatures in the nation’s capital; On Saturday, the maximum temperature at the Safdarjung station was 16.4 degrees Celsius (° C), three degrees below normal and nearly four below Friday’s reading of 20.3 ° C. The minimum temperature on Saturday was 15.2 degrees Celsius, with the difference between the maximum and minimum temperatures on Saturday being just 1.2 degrees Celsius.
“An interesting thing to note is that the difference between daytime and nighttime temperature is only one degree. It’s very unique, ”Jenamani said.
IMD said fairly widespread rainfall is expected to continue in Delhi on Saturday and decrease thereafter. According to the IMD weekly forecast, cloudy skies with light rain are expected on Sunday.
Air quality in the city also improved on Saturday, thanks to the rain. Delhi recorded an Air Quality Index (AQI) of 91 (satisfactory), an improvement from Friday’s AQI of 182, according to the Central Pollution Control Board’s (CPCB) 4 p.m. bulletin.
The CPCB classifies an AQI of zero to 50 as “good”, 51-100 as “satisfactory”, 101-200 as “moderate”, 201-300 as “poor”, 301-400 as “very bad” and above 400 as “severe”.
The air quality monitoring center of the Union Ministry of Earth Sciences, System of Air Quality and Weather Forecasting and Research (Safar), attributed the improvement in the AQI to the high dispersion of pollutants and wet deposition of particles from rain. “From the 9 (Sunday), the air quality is likely to deteriorate due to the gradual decrease in maximum and minimum temperatures as well as wind speed, all contributing to a low dispersion of pollutants”, indicates prediction.
Following rains, congestion was reported in various parts of the capital. Areas such as New Friends Colony, Dabri, Bindapur, Tilak Nagar and Chattarpur have been flooded, traffic officials said.