A powerful pre-monsoon thunderstorm accompanied by torrential rain and fierce winds swept through Kolkata and several adjoining districts of South Bengal, bringing a sudden break from the scorching summer heat wave but leaving behind a trail of urban disruption.
The severe weather event, which hit the region in the afternoon, recorded peak wind speeds of up to 88 kmph in some areas. While the downpour provided immediate relief from intense humidity, high-velocity squalls caused widespread infrastructural damage, uprooted massive trees, and temporarily halted major transit operations across the metropolitan area.
The Severe Weather Event: What Happened?
The weather took a dramatic turn on Friday afternoon as dark, heavy thunderclouds gathered rapidly over the city sky, dropping visibility to near-zero conditions within minutes. According to the Regional Meteorological Centre (RMC) in Alipore, the storm hit with maximum intensity during the mid-afternoon hours, bringing heavy downpours that quickly flooded low-lying streets and thoroughfares.
The defining feature of the storm was the violent wind speed. The Alipore weather station clocked peak wind speeds touching 88 kmph, while Dum Dum recorded gusts up to 74 kmph. This severe squall line quickly overwhelmed municipal infrastructure, snapping overhead wires, tearing down commercial billboards, and shattering glass facades on several prominent commercial properties, including the South City Mall.
Impact on City Traffic and Uprooted Trees
The combination of heavy rain and powerful winds resulted in major logistical challenges on Kolkata’s roads. More than 60 trees were reported damaged or completely uprooted across major corridors.
Key Areas Affected:
- Southern Avenue: Multiple roadblocks occurred after massive tree trunks collapsed across the lanes, completely blocking vehicular movement. In some instances, falling branches landed on parked vehicles along the avenue.
- Central & South Kolkata: Stretches like Rashbehari Avenue, Harish Mukherjee Road, AJC Bose Road, and Park Street reported fallen branches and uprooted trees that ground traffic to a halt.
- Waterlogging: Traditional bottlenecks in central and northern parts of the city, such as Thanthania and Chandni Chowk, experienced hours of waterlogging, forcing motorists to navigate carefully with headlights on.
Municipal teams from the Kolkata Municipal Corporation (KMC) and state disaster management groups were quickly deployed to the affected zones. Equipped with emergency tree-cutters and heavy machinery, personnel worked through the evening to clear the blocked arterial roads and restore normal traffic flow.
Mass Disruptions to Public Transit
The sheer intensity of the afternoon squall briefly paralyzed the city’s primary transport links:
- Flight Operations: Flight arrivals and departures at the Netaji Subhash Chandra Bose International Airport were suspended for nearly an hour due to severe wind shear and low visibility. Around 20 flights faced delays, and multiple incoming flights had to be safely diverted to nearby airports like Agartala and Bhubaneswar.
- Metro Services: On the busy Blue Line, services were temporarily disrupted. Strong winds damaged a portion of the overhead shade structure at the Shahid Khudiram Metro station in South Kolkata, leading to rainwater entering the platform area and halting trains between specific stations for about 30 minutes.
- Suburban Trains: Rail networks faced similar hurdles. Tree branches collapsed onto overhead electrical wires along the Sealdah South section and the Bandel-Katwa branch, interrupting local train services until railway engineers cleared the tracks.
Why It Happened: The Meteorological Reason
Meteorologists at the Alipore Met Office attributed this violent weather shift to strong moisture incursion from the Bay of Bengal combined with an atmospheric cyclonic circulation tracking over central India.
The accumulated surface heat and high humidity over South Bengal created highly unstable atmospheric conditions, aiding the rapid formation of massive thunderclouds. These cloud towers reached heights of nearly 15 kilometers, resulting in the intense localized squalls, locally known as Kalbaisakhi or Nor’westers, typical for this transition season.
Key Takeaways
- Peak Storm Intensity: High-velocity winds reached up to 88 kmph in parts of Kolkata, accompanied by sudden heavy rainfall.
- Widespread Road Blocks: Over 60 trees were damaged or uprooted, notably causing heavy blockages on Southern Avenue and Harish Mukherjee Road.
- Transit Delays: Flight movements were suspended for an hour, metro services faced short disruptions, and suburban rail lines suffered delays due to overhead wire issues.
- Official Advice: The India Meteorological Department (IMD) has advised citizens to remain indoors during active lightning storms and cautioned fishermen against venturing into open coastal waters.
Frequently Asked Questions (FAQs)
Q1: What caused the sudden heavy storm in Kolkata? The storm was triggered by a combination of high atmospheric heat, intense moisture entering from the Bay of Bengal, and a cyclonic circulation that caused rapid thundercloud formation over South Bengal.
Q2: Which parts of Kolkata faced the most damage to trees? Southern Avenue, Harish Mukherjee Road, Park Street, AJC Bose Road, and the Maidan area experienced significant tree falls and blocked roads.
Q3: Were flight and train services affected? Yes. Flight operations at Kolkata Airport were suspended for about an hour due to poor visibility, and suburban train services on some routes were delayed by branches falling on overhead power lines.
Q4: Is more rain expected in the coming days? The weather office indicates that while intermittent light-to-moderate showers may continue over the next two days, the overall intensity of the squalls is expected to gradually decrease.
