In a regular world, April would be a month of crackling and often lethal electric storms with gales followed by intense showers — called kalbaisakhis or norwesters — cooling down a fiery day in a matter of seconds. These dramatic evening storms inspired great poets like Rabindranath Tagore and Kazi Nazrul Islam, who celebrated their thrilling advent, their regenerative power with upbeat metaphors that Bengalis never tire of revisiting.

The kalbaisakhi, however, is yet to surface in 2023. The reason: An extra-strong dry weather system blowing in from the north-west, stonewalling the feebler moisture-laden southern winds, making Kolkata hotter than Rajasthan’s desert right now.

Bengal’s capital, along with the districts, is under a climate siege — wrestling with a vicious and sustained heat wave that shows no sign of letting up. Yesterday, it hit 40.6 degrees Celsius and today will be no different. “What is in store for Kolkata will be known tomorrow (April 21). But even if there is no rain, a slight dip in the Celsius is likely,” G.K. Das of Indian Meteorological Department (IMD), Kolkata, told The Telegraph.

“The current heat wave in Kolkata and West Bengal may be a symptom of climate change, but it is important to analyse long-term trends in temperature and weather patterns to determine the extent to which climate change is contributing to this heat wave,” Anjal Prakash, climate expert and Research Director at ISB, Hyderabad, said in an exclusive chat with CNBC TV18.

“It is also important to note that while climate change is likely to result in more frequent and intense heat waves in the future, there will still be natural variability in weather patterns," he added.

Since April 13, 2023, the highest recorded temperatures in Kolkata have been consistently ranging between 40-43 degrees Celsius, as per AccuWeather. Last year in the same period (April 13-20), the temperatures were an almost salubrious 36-37 degrees C with a solitary 40-degree reading popping up only on April 15.

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What is kalbaisakhi?

Kalbaisakhi is a regional midsummer rain-and-thunder event which occurs in West Bengal, Bihar, Jharkhand, Odisha and Tripura, as well as Bangladesh, in April-June — at times even arriving early in March. “The arrival of the kalbaisakhi or pre-monsoon thunderstorms in Kolkata and West Bengal is primarily influenced by regional weather patterns, such as the movement of the jet stream and the location of high-pressure systems,” Prakash explained.

Long ago, Bangladeshi poet Farrukh Ahmed likened it to “a terminator that could fight against the tyrannical injustice towards harmony” in his poem Boishakh.

The delay and its aftermath

On a more prosaic note, Soma Sen Roy, a scientist with IMD, said on April 18: “East India particularly, both the sub-Himalayan and Gangetic plain regions, is continuing to see the worst heat waves.” A weather system is classified as a heat wave when temperatures range at 40 degrees and above and are 4.5 degrees above normal levels. For severe heat waves “it has to be a departure of 6.4 degrees,” as per Sen Roy.

The state’s Regional Met Centre (RMC) Director Sanjib Bandopadhyay, while admitting this was exceptional and unusually dry weather, pointed out it’s not a first for Kolkata, as back in 2016 the city had seen eight days of unrelenting 40 degrees-plus. We are already on the eighth day as of April 20, 2023. So, going by that, a new record is on.

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In Kolkata, the dry heat is likely to continue till Monday, April 24, when the southerlies may just despatch that bleak feeling. The districts of Bengal may get the rain relief earlier. Hearteningly, it rained a bit in Darjeeling yesterday.

Where does El Niño figure in all this?

“El Niño, which is a climate pattern characterised by warmer than usual ocean temperatures in the central Pacific Ocean, can also influence weather patterns globally, but its specific effects on the timing of kalbaisakhi in Kolkata and West Bengal are unclear,” Prakash said.

As the sun seeps into the concrete and clueless crows build nests imagining it is springtime, here are a few avatars of Kolkata’s early-onset summer of 2023:

Loadshedding is back

At 11 pm on Sunday (April 16), a group of males rushed into a mall in central Kolkata and ‘occupied it’ — to escape a prolonged power cut. The video went viral, even showing an individual napping on his knapsack on the mall’s ground floor.

The local power utility CESC professed it was unable to take beyond the “sanctioned” overload of a zillion air-conditioners whirring at the same time. An electronics goods store said AC sales are up “100 percent” in April over March. Secondhand ACs (Rs 10,000 and below) are also flying off the shelves as are stand fans.

Power cuts for up to 6.5 hours have taken Kolkatans back to the Calcutta of the seventies, when ‘loadshedding’ was the thing, and hurricanes, well.. meant kerosene lamps. Cut to 2023 (when GenZ only knows hurricanes as killer American storms), with higher temperatures, hapless apartment residents were spotted sitting in nearby parks rather than remain indoors — till the power got restored.

West Bengal Power Minister Aroop Biswas, in an ad hoc move, summoned the CESC brass and told them to use “high-end generators” in areas where transformers are blowing up, to ensure uninterrupted power supply.

Online classes are back

In another throwback — albeit only to the recent past — online classes have returned. West Bengal CM Mamata Banerjee issued a seven-day holiday diktat for all educational institutions, including private ones, from Monday (April 17) without warning. She also pulled ahead the summer vacation to May 2 from end-May, sending school authorities into a tizzy as the new academic session has just begun.

#KolkataHeatwave: Teachers' organisations of different varsities in West Bengal expressed concern over the closure of educational institutions in the state, citing that it will affect the academic schedule. https://t.co/n0NATs1Io8

— National Herald (@NH_India) April 18, 2023

Those preparing for the Class 12 board exams are most affected. A teacher at The Heritage School, alone in a classroom with her laptop and water bottle, said, “It reminds me of COVID times.” On April 17, a few Class 12 students had even ventured into the school despite the government order. “Online classes just do not work for those of us who are preparing for the boards. We have come to collect books from the library and have a session with our teacher,” one of them told ABP Live. They were not wearing school uniforms.

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Walkers and gig workers

The bus operators in Kolkata have reduced services and rejigged schedules, with the operators’ union advising against service between 1-3.30 pm as bus drivers and conductors have reported heatstroke-like symptoms, The Times of India reported. The number of riders has also drastically dropped.

It’s a different story for gig workers, it seems. Aarti, who works with Zomato, said, “There is less resting time for me. More people are ordering food as they do not want to venture outdoors.” Anup Mukerjee, a guard at the Dhakuria Lakes, a top draw for morning and evening walkers in south Kolkata, said, “I’ve been working here since 2012. Never have I seen such low numbers of walkers, both in the morning and evening.”

While there is no official data on casualties in the wake of the heat wave, one person in his sixties is reported to have collapsed and died on April 16 while walking in the book hub of central Kolkata. Hospitals have seen a spike in the number of elderly patient admissions with dehydration related complaints and urinary tract infections.

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February 2023, at an average temperature of 29.54 degrees C, has been recorded as the hottest February in India since 1901. March 2022 (average temperature 33.1 degrees C) was the hottest among Marches, again since 1901. We will have to wait a few more days to see if this April lives up to T.S. Eliot’s “cruellest month” tag in Indian, or at least Kolkata’s, recorded weather history.

(All pictures by Shoma Bhattacharjee)

First Published:Apr 20, 2023 7:47 PM IST