A city scalded by one of the most brutal and lengthy heat assaults in years had its prayer answered on Monday evening, when it was lashed by rain accompanied by gusts of wind.

The storm led to flight diversions, stopped trains in their tracks and slowed traffic across the city. At least seven trees were uprooted. Waterlogging was reported from several parts.

The thunderstorms claimed lives in the districts. At least two people were reportedly killed in lightning strikes in Purulia. Two others died in Nadia in a wall cave-in.

The Met office recorded around 50mm of rain in Alipore between 7pm and 8.30pm on Monday. In Met parlance, 60mm in 24 hours qualifies as heavy. Ballygunge got around 90mm between 7pm and 9pm, according to the Kolkata Municipal Corporation (KMC).

The last time the city was rainier was between October 3 and 4 last year, when parts of Calcutta got over 100mm of rain.

In Calcutta, what started as a drizzle a little after 7pm had by 8pm transformed into a fearsome storm. The rain blurred visibility. Billboards fluttered from scaffoldings, and doors and windows banged shut every now and then.

Pedestrians struggled to keep their umbrellas steady in the wind and the incessant streaks of lightnings looked threatening.

Flights were stalled for around an hour between 7.20pm and 8.24pm, said an official of the Calcutta airport. Fourteen city-bound flights had to be diverted because of the strong winds and lightning.

“Ten flights took off late mainly because of the strong winds. Normal operations resumed at 8.25pm,” he said.

Thanks to the excruciating heat spell, the yearning for rain was so much that many people got drenched on the roads. Many others, who were indoors, flocked to balconies and terraces to soak in the showers.

Richeek Biswas left his workplace in central Calcutta around 7.45pm. The Mahatma Gandhi Road Metro station is less than a five-minute walk from his office. “I was not
carrying an umbrella. The rain was so heavy that I had
to come back to the office. Apart from the rain, the streaks of lightning kept coming one after another,” said Biswas.

The intensity of the showers had marginally dipped by 9pm but there was no let-up in the gusts of wind and rumblings of thunder.

The Met office recorded a gust clocking around 75kmph in Alipore around 9pm.

Local train services in the Sealdah South section were crippled after parts of a tree damaged the overhead equipment.

Trees fell in at least seven places in Calcutta, a KMC official said.

“Trees fell along Cossipore Road, Alimuddin Street, Hughes Road (Tangra), KG Bose Sarani (Narkeldanga), Rai Charan Pal Lane (Gobra) and Mayurbhanj Road (near Ekbalpore),” he said.

A tree fell inside the CGO complex in Salt Lake, said an official of Bidhannagar Municipal Corporation.

The showers led to waterlogging in some pockets. Traffic considerably slowed on busy roads like Strand Road, BB Ganguly Street, Central Avenue and Diamond Harbour Road.

Narrower streets and alleys across the city were also waterlogged. Around 9.15pm, Ibrahimpur Road, near the Jadavpur 8B bus stand, was submerged under ankle-deep water. Ditto for Becharam Chatterjee Road in Behala.

But the relief that the thunderstorm brought far outweighed any other distress it caused. Images of the rain-starved Champaneer village from Lagaan, the 2001 Aamir Khan-starrer, enjoying long-awaited showers flooded social media. “Karunadharaye esho he (come in streams of mercy),” read a post, borrowing from Tagore.

The storm brought the only proper rain that the city has seen in almost 50 days. Between March 20 evening and March 21 evening, the city had received around 20mm of rain. April — apart from being unusually hot — was exceptionally dry as well. All that the city got was a drizzle — 0.5mm in Alipore — on April 7.

The Met office linked the showers to three factors and said more are likely in the next few days.

“A cyclonic circulation lies over south Jharkhand and neighbouring areas at 0.9km above the mean sea level. A trough runs from above the cyclonic circulation over south Jharkhand to west Madhya Pradesh at 0.9km above the mean sea level. There is a strong moisture incursion from the Bay of Bengal. Under the influence of these factors, thunderstorms are likely in south Bengal on Tuesday and Wednesday as well,” said a Met official.