Over 400 flights delayed, 26 cancelled as heavy rain pounds Delhi; IndiGo, Air India, SpiceJet issue advisories

Over 400 Delhi-bound flights, including three international, were diverted while 26 others were cancelled on Monday after heavy rain and thunderstorms disrupted operations at Indira Gandhi International Airport, according to data from flight tracking website FlightRadar24.

The data showed that 413 flights were delayed, while 26 were cancelled. Several flights were diverted to airports including Jaipur, Chandigarh and Lucknow.

The diversions came as heavy rain lashed several parts of Delhi and surrounding regions, resulting in waterlogging and traffic snarls across the city.

The India Meteorological Department (IMD) had issued a red alert for heavy rain in parts of the capital and a yellow alert for moderate rain in other areas. Thunderstorms, lightning and winds of 30-40 kmph were also expected in parts of Delhi.

Airlines issue travel advisories

All major airlines warned passengers that adverse weather could affect flight schedules and advised them to check their flight status before travelling to the airport.

IndiGo said bad weather over Delhi had affected flight schedules and asked passengers to check their status on its website or app before leaving for the airport. It also advised travellers to allow additional time because of slower road conditions.

SpiceJet said bad weather in Delhi could affect departures, arrivals and consequential flights, and asked passengers to check their flight status.

Air India also advised passengers travelling to and from Delhi to check the latest flight status before heading to the airport, warning that adverse weather could affect operations.

Heavy rain causes waterlogging, traffic snarls

The rainfall also disrupted road traffic in several parts of Delhi-NCR, with commuters reporting waterlogging and traffic congestion.

IMD has predicted continued spells of rain in Delhi on Monday. Conditions are expected to turn largely dry from Tuesday, with little or no rain forecast for most of the remainder of the week.

For Tuesday, very light rain is possible in the afternoon. Very light to light rain is expected at a few places on Wednesday, with another spell possible from afternoon to evening and moderate rain likely at isolated locations.

From Thursday through Sunday, no rain has been forecast, with partly cloudy skies expected.

Delhi recorded a minimum temperature of 27.8 degrees Celsius at Safdarjung on Monday, 1.4 degrees above normal. The Ridge recorded the lowest minimum temperature in the city at 24 degrees Celsius.

Broader pattern of increasing monsoon variability

Dr Vishwas Chitale, Fellow at the Council on Energy, Environment and Water (CEEW), said the intense rainfall was part of a broader pattern of increasing monsoon variability.

"The intense rainfall being witnessed across Delhi NCR today is part of a larger concern around the increasing variability of the monsoon," Chitale told Mint.

He said CEEW's long-term analysis showed that the monsoon was becoming increasingly erratic in its timing, distribution and intensity, rather than simply becoming wetter or drier.

"Across India, 64% of tehsils have seen an increase in the frequency of heavy rainfall days in the last decade compared to the 1982 to 2011 baseline, while 23% of districts, including New Delhi, have historically experienced a high frequency of both deficient and excessive rainfall years," he said.

Chitale said intense rainfall could be particularly disruptive for highly urbanised areas such as Delhi-NCR, where short spells of heavy rain can overwhelm drainage systems and affect mobility and essential services.

"For a highly urbanised region like Delhi NCR, short bursts of intense rainfall can overwhelm drainage systems, disrupt mobility and essential services, and significantly increase urban flood risk, particularly as concretisation reduces the ability of the land to absorb water," he said.

He called for climate-informed drainage infrastructure, restoration of urban water bodies and natural drainage channels, better rainwater harvesting and hyperlocal flood early-warning systems to deal with increasingly intense rainfall events.