Just 1 'heavy'-rain day in Delhi so far

NEW DELHI: When the monsoon arrived on June 30, the city saw its first and only "heavy" rain spell. Between 8.30am on June 30 and 8.30am on July 1, Delhi recorded 117.2mm of rainfall, making it a "very heavy" rain day.
However, intense rain activity has mostly eluded Delhi this monsoon since July 1. In contrast, monsoon 2021 saw seven "heavy" rain days, including two "very heavy" rain days. Met officials said usually, there are only two or three "heavy" rain days in a season.
India Meteorological Department (IMD) considers the monsoon season from June to September. June 2021 saw "light" to "very light" showers and ended at a deficit of 67%. Safdarjung, the city's base weather station, logged 24.5mm of rainfall against the normal of 74.1mm.
July saw four "moderate" rain days along with light rain activities. IMD data shows that Safdarjung recorded excess rainfall in July, mainly due to the "very heavy" spell of 117.2mm of rainfall recorded on the first day of the month. The city recorded 286.3mm of rainfall in July against the normal of 209.7mm, making it an excess of 37%.
No major rain activity was observed in August, which witnessed a deficit of 83%. It logged just 41.6mm of rainfall, the lowest in at least 14 years. The month failed to see even a "moderate"rain day.
In the past 10 years, the city has mostly seen two "heavy" rain days during monsoon, while no such day was observed in 2020, 2019, 2018, 2016 and 2012. Met officials said there was no prevalent trend on the rainfall pattern during monsoon as it depended on the weather system.
A Met official said, "There are normally two or three heavy rain days in a monsoon season. As there was no low pressure system in Delhi and the monsoon trough remained away on most days in August, no intense rain activity was recorded."
As monsoon withdraws from Delhi in September, officials said it was difficult to predict if the city would receive heavy rain in the month. The normal date for the withdrawal of monsoon is September 25.
According to IMD, "trace" to 2.4mm of rainfall recorded in 24 hours is considered "very light", while "light" rainfall is between 2.5mm and 15.5mm. Rainfall recorded between 15.6mm and 64.4 mm is declared "moderate", while "heavy" rainfall is from 64.5mm to 115.5mm. The criteria for "very heavy" rainfall is between 115.6mm and 204.4mm.