The city recorded its heaviest September rainfall in 16 years, with 121 mm recorded at the airport observatory till 5.30 pm on Sunday, according to India Meteorological Department’s (IMD) data.
The rainfall was highly uneven across the city as the Sector 39 observatory, just a few kilometers away, recorded only 38.3 mm during the same period. The airport and Sector 39 observatories are located at the eastern and western ends of the city, respectively. IMD uses rain data from both the observatories to calculate the average to prepare their month-end report for the city. In Panchkula, the Automatic Weather Station recorded 18.5 mm rainfall.
The 121 mm recorded at the airport was the highest September rainfall at the observatory since 2010, when 122.1 mm was recorded on September 22. The highest-ever rainfall recorded on a September day in the city since 1954 was 235 mm on September 26, 1955, followed by 171.6 mm on September 21, 1962.
IMD’s Chandigarh director Surender Paul attributed Sunday’s rainfall to the monsoon system combining with easterly winds, resulting in significant showers over parts of the region. Light rain is likely to continue from Monday onwards. Another spell of heavy rain is expected around Wednesday or Thursday, as per initial forecasts.
Regarding the sharp variation in rainfall between the two observatories, Paul said that towards the second half of the monsoon, cloud distribution plays a role in deciding which part of the city gets more rain. While such hyperlocal effects are difficult to predict, Paul said it is not uncommon for some sectors to receive substantial rainfall in September while others receive much less.
Heaviest spell this monsoon
The spell was also the heaviest rainfall recorded in Chandigarh this monsoon. Before Sunday, the highest was 92 mm on July 10. According to data from the Sector 39 observatory, Chandigarh has received 697.6 mm rainfall so far this year, which is 19% below normal for the corresponding period. September is the last monsoon month in the city, with its withdrawal usually announced in the last week of the month.
The maximum temperature fell from 36.8°C on Saturday to 34.8°C on Sunday, although it remained 2°C above normal. The minimum temperature dropped marginally from 25.1°C to 24.9°C, which was 1°C below normal.
Over the next three days, the maximum temperature is expected to remain between 34°C and 35°C, while the minimum is likely to stay between 24°C and 25°C.