Archive · 11 Aug 2026
Sudden Heavy Rain Floods Kolkata Roads, Cripples Traffic
One evening, a big and sudden rainstorm hit the city of Kolkata in India.
The rain was so strong that it flooded the streets very quickly.
Some places got more than 150mm of rain in just one hour, which is a lot of water.
The city's drains could only handle about 6mm per hour, so they could not keep up.
Many roads had water up to people's knees, and cars and buses could not move easily.
People who were going home from work got stuck on their journeys for a very long time.
Taxi rides also became much more expensive because of the bad weather.
The weather experts were surprised because they did not expect so much rain that day.
They said the storm was caused by the monsoon winds and a big swirling pocket of air over the sea.
The storm finally eased after a few hours, but the city had a very difficult evening.
Belgachia in north Calcutta received 150mm of rain and Thanthania 115mm in just over an hour, according to Kolkata Municipal Corporation pumping station readings.
By 9pm, large parts of Calcutta from Dum Dum in the north to Chetla in the south were under water, with roads such as Central Avenue, Camac Street and Lee Road waterlogged.
The Met office had predicted only light to moderate rain but issued a second nowcast around 8:35pm warning of moderate thunderstorm with intense rain and gusty wind.
Commuters were stranded, with one office-goer, Apurba Roy, taking two-and-a-half hours to reach home, double his usual travel time, and app cab fares surging to ₹510.
Met officials attributed the sudden rain to the monsoon flow, the position of the monsoon trough and a cyclonic circulation over the Bay of Bengal.
The city's drainage system can drain only about 6mm of rain per hour, while the Met office classifies 60mm in 24 hours as heavy rain.
- Who
- Residents and commuters of Calcutta (Kolkata), along with officials of the Kolkata Municipal Corporation and the Met office.
- What
- A sudden spell of heavy thunderstorm rain flooded roads and crippled traffic across large parts of the city.
- When
- Monday evening, most intense between 8pm and 9:15pm, with a fresh spell beginning around 10pm.
- Where
- Calcutta (Kolkata), especially north Calcutta areas such as Belgachia and Thanthania; flooding spread from Dum Dum to Chetla.
- Why
- The Met office attributed the rain to the monsoon flow, the position of the monsoon trough and a cyclonic circulation over the Bay of Bengal.
- Rainfall in Belgachia
- 150mm in just over an hour
- Rainfall in Thanthania
- 115mm in just over an hour
- Rainfall in Ballygunge
- 40mm
- Rainfall in Southern Avenue
- 25mm
- Rain in Alipore till 8:30pm
- Around 20mm
- City drainage capacity
- About 6mm per hour
- Peak intensity
- 8pm-9:15pm
- Cab fare Esplanade to Behala
- ₹510 (usual ₹300-₹350)