Delhi witness its coolest May in 36 years with copious rainfall

According to the India Meteorological Department (IMD), Delhi experienced its coolest May in 36 years, with abundant rainfall leading to an average maximum temperature of 36.8 degrees Celsius. In May 1987, the average high temperature in Delhi was 36 degrees Celsius, making this year’s temperature the lowest since then, as stated by Kuldeep Srivastava, the head of IMD’s regional forecasting division.

Out of the 31 days in May, only nine days had maximum temperatures exceeding 40 degrees Celsius, and heatwave conditions affected certain areas of the national capital for two days. Srivastava highlighted that the Safdarjung Observatory, which is representative of Delhi’s weather, did not record any heatwaves during this year’s pre-monsoon season, a phenomenon that hasn’t occurred since 2014.

During the same period last year, there were 13 heatwave days in Delhi, with nine in April and four in May. In comparison, this year had only one heatwave day, while 2020 and 2019 had four and one heatwave days, respectively.

May is typically the warmest month in Delhi, with a mean maximum temperature of 39.5 degrees Celsius. However, this year it received 111 mm of rainfall, which is 262 percent higher than the long-term average of 30.7 mm. This makes it the fourth-highest monthly rainfall on record, following the rainfall figures of 165 mm in 2008, 144.8 mm in 2021, and 129.3 mm in 2002.

The increased rainfall and below-normal temperatures during the pre-monsoon season are attributed to stronger-than-usual western disturbances originating in the Mediterranean area. These disturbances result in unseasonal rain in northwest India. Normally, five to six western disturbances are observed in the northern plains during April and May, but this year witnessed 10 mostly strong disturbances, according to Srivastava.

While this pattern is unusual, Srivastava stated that it is challenging to establish a direct link to climate change without sufficient data and a clear trend. Delhi received 184.3 mm of rainfall during the pre-monsoon season (March to May), which is 186 percent above the normal rainfall, as reported by the IMD.