New Delhi, May 26 -- Gusty winds of speeds over 80km/hr ripped through Delhi on the intervening night of Saturday and Sunday, bringing with them severe thunderstorms and heavy rainfall-all of which created unfavourable conditions for flight operations, delaying over 400 flights through the day and leading to tens of diversions, officials aware of the developments said. Airport officials said the diversions were necessitated from 11.30pm on Saturday, and continued until around 4am on Sunday. The average delay time of each flight was 27 minutes, according to flight tracking website FlightRadar24. "A total of 49 flights, including 17 international flights, were diverted during this period," an airport official said, adding that delays continued beyond 4am, into the second half of the day as well, due to a cascading effect. The flights were impacted due to wind shear-strong winds blowing in the opposing direction and rain, officials said. Both take-offs and landings are impacted in such a scenario. Lightning too poses a risk for flights. On the same day, visuals emerged on social media of an external tensile fabric, used to cover the area outside the arrivals hall at Terminal-1, tearing apart due to water accumulating on top of it. The water is then seen gushing onto the road and towards the arrivals hall. Airport operator Delhi International Airport Limited (Dial), however, described it as the "design's natural response to prevent excessive water retention." A Dial spokesperson said, "Delhi experienced an intense thunderstorm accompanied by heavy rainfall during the intervening night of May 24th, 2025. The city recorded over 80mm of rain with wind speeds touching 70-80 km/hr within a short span of 30 to 45 minutes around 2am. This sudden and concentrated downpour led to temporary water accumulation in and around IGI Airport, briefly impacting operations." "As a part of the design's natural response to extreme conditions and to prevent excessive water retention, a section of the external tensile fabric at the T1 Arrival forecourt adjusted under pressure, thereby aiding in water dispersal. There was no structural compromise to other parts of the terminal." India Meteorological Department data showed the airport recorded a maximum wind speed of 72 km/hr at around 2am and received 68.5mm of rainfall until 8.30am. Roads leading up to the airport were waterlogged until the afternoon. "Last night's adverse weather in Delhi, continues to affect operations due to airside congestion. While conditions have improved, delays in departures, arrivals and ground handling may persist. We recommend planning your travel with sufficient buffer time as routes to the airport may be affected by waterlogging," said IndiGo in a statement on X. Air India also issued an advisory. "Thunderstorms and gusty winds last night impacted flight operations across parts of northern India. Consequently, some flights to and from our Delhi hub had to be diverted...While we are making every effort to minimise the disruption, we request our guests to check the status of their flights before heading to the airport," it said....