The Calcutta skyline wears an apocalyptic look moments before the thunderstorm struck on Thursday evening. Picture by Ankit Datta
Calcutta survived its sultriest day of the summer with a thunderstorm and an all-time record in power consumption that might not last the weekend.
The weather office has sounded an alert for an unprecedented fourth heatwave of the season by Saturday, a prospect even more daunting than what the city had to endure on Thursday.
“With monsoon delayed, we expect northwestern winds to reach the state and trigger a rise in temperature. The mercury could hit 43 or 44 degrees Celsius in the western districts of south Bengal over the next two days. The temperature in Calcutta could reach around 40 degrees,” said G.C. Debnath, director of the India Meteorological Department, Calcutta.
A heatwave is declared when the maximum temperature shoots up five notches above normal to hit 40 degrees Celsius or more.
Before the thunderstorm hit town, Thursday was easily the most uncomfortable day of the season. The maximum temperature rose from 36.8 on Wednesday to 38.1, four degrees above normal, but what made Calcuttans sweat bucket loads was the humidity.
Relative humidity, which indicates the levels of moisture saturation in the air, stayed in the region of 70 per cent for most of the day to push up the discomfort index to 69.5 degrees Celsius, a gruelling 15 notches above the comfort level.
The discomfort index is a complex calculation meant to represent the combined effect of heat and humidity on the human body.
If any proof was needed of how bad the weather was, the power consumption statistics showed how the city fought the heat assault. Air-conditioners and fans groaned through the day across homes, offices and business establishments, taking power demand in the CESC-served areas to an all-time high of 2,042MW in the afternoon.
The power utility successfully met the challenge of supplying uninterrupted power to its 28 lakh consumers spread across 567sq km by importing 904MW in addition to the 1,227MW generated by its plants.
Since April, it was the fifth time that the consumption record had been broken, mirroring the city’s woes in a summer marked by a spell of heatwave each in March, April and May. The one in April had lasted an agonising 10 days, the longest in memory.
CESC officials attributed the surge in power consumption to the use of air-conditioners by the majority of the domestic consumer base.
Apart from the overworked ACs, Calcutta’s source of relief was the storm in the evening that originated in Bankura in the afternoon and kicked in from the northwest direction a little after 6pm. The wind speed peaked at 56kmph for two minutes from 6.33pm.
The Alipore Met office recorded 2mm of rainfall between 5.30pm and 8.30pm, but the Calcutta Municipal Corporation figures were significantly higher in many parts of the city.
Trains were stranded and traffic stalled on some Calcutta roads as trees were uprooted by the tempest, the second in as many days. Several long-distance trains were delayed after a tree fell on the tracks just before the Howrah-bound Rajdhani Express was to pass Chandanpur in Hooghly, around 50km from the city. The train was stranded there from 6.05pm till the tree was removed around 7.30pm.
“Since the tree fell on the chord line, several other long-distance trains, including the Sealdah-bound Rajdhani Express, were stuck. Normality was restored around 7.30pm,” a railway official said.
An uprooted tree on BB Ganguly Street stalled traffic for more than 10 minutes. Trees also fell on the Rashbehari connector, Basanti highway and Moti Sil Street.
In the absence of monsoon, which usually arrives in Calcutta between June 8 and 10, thunderstorms are the city’s only hope with a heatwave looming over the weekend.
Cyclone Nanauk, centred in the Arabian Sea 700km from Mumbai, has been holding monsoon hostage this year, delaying its arrival in the city.
“Moisture supply is abundant in the city at the moment because monsoon winds have reached north Bengal and there is a feeble trough of low pressure over the state. Although monsoon is still to arrive in the city, thunderstorms are possible because both heat and humidity are present,” said Met director Debnath.
Electricity consumption hits all-time high before storm brings relief
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