Why a Few Hours of Heavy Rains in Delhi Became an ‘Extreme Weather Event’

On the intervening night of 27 and 28 June, the national capital of Delhi received 228.1 mm of rainfall – recorded until 8:30 am on Friday.

The rain broke an 88-year-old record, becoming the second highest June rainfall ever recorded at the Safdarjung observatory of the India Meteorological Department (IMD).

Though lasting only a few hours, the rain resulted in the loss of at least eight lives, including a cab driver who died outside the Indira Gandhi International Airport’s Terminal 1 after a roof collapsed, and three labourers who got trapped under a wall at a construction site in Vasant Vihar. Many others were reportedly injured.

The Delhi rain also led to economic losses for many as roads were waterlogged, trees uprooted from the ground, and multiple personal and public properties were damaged.

While chatter about the need to build climate-resilient infrastructure to protect our cities from ‘extreme weather events’ took over social media on Friday, The Quint reached out to experts to understand how a spell of rainfall that only lasted a couple hours became an ‘extreme weather event’.

‘Delhi Rain on Friday Crossed All Parameters of Extreme Weather Event’

According to the IMD, within a span of 24 hours, if a place receives 64.5-115.5 mm rain, it’s a heavy rainfall. If it receives 115.6-204.4 mm rain, it’s termed as very heavy rainfall, and if it crosses 204.5 mm rain, it’s categorised as extremely heavy rainfall.

Abinash Mohanty, Sector Head, Climate Change & Sustainability at IPE Global, and Expert Reviewer of IPCC- AR(6), said,

“This specific spell of rainfall was at a record level of 228 mm, which was the average precipitation level expected for all of June. It qualified as an extreme weather event because more than one month's average rainfall was received in a matter of a few hours.”

Speaking to The Quint on the changing patterns of rainfall in the country, Dr Vishwas Chitale, Senior Programme Lead, Council on Energy, Environment and Water, had earlier said that climate change is responsible for causing these sudden and intense outbursts of rain, that last only for a short while but cause significant damage across many sectors.

However, Dr Chitale had added that western disturbances over North India also have a role to play in this erratic rainfall.

Another cause, he had added, was that with increasing marine heat waves, our oceans are warming up faster than ever, leading to more evaporation, that in turn causes more frequent and unevenly distributed rainfall.

‘Our Unpreparedness Was Not Justified’

But could we have done something more to deal with this extreme weather event? When the IMD forecasts rain, is it possible for them to forecast the intensity of the rain as well to help better prepare for it?

Raghu Murtugudde, Earth Systems Scientist at IIT Bombay, told The Quint, “The systems do help recognise which regions will receive rainfall, but it's not as precise to say that Delhi airport will receive this much rainfall, or another area will not receive rainfall.”

Going forward, what we need is a “hyper granular risk assessment that closely tracks climate events,” according to Mohanty.

“The (intensity of the rainfall) doesn't justify that we were not ready for this. We need climate resilient infrastructure, of course. What we also need is impact-based forecasting that takes into account wind, weather, etc, to forecast even the intensity of the event and its probable impacts on hotspots.”

Abinash Mohanty

After the rains wreaked havoc, emergency rescue teams were brought into action across the city.

The National Disaster Response Force (NDRF) and the Delhi Disaster Management Authority (DDMA) have been working in tandem with civic authorities to prevent any more casualties.

The Delhi government opened a 24-hour working control room to assist Delhi residents impacted by the rain.

The Union Civil Aviation Minister Ram Mohan Naidu Kinjarapu took cognisance of the incident at the Delhi airport and assured citizens of all safety measures being undertaken. 

While the efforts that followed the event were much needed, Mohanty emphasised on the need of a climate and disaster risk observatory that is ready 24x7 and 365 days for disaster management.

He added,

“Since these events are only going to be more frequent, we need a plan to keep NDRF, evacuation teams, etc, always ready, while also making citizens aware and better prepared.”