Kolkata and its surrounding areas were hit by an unprecedented overnight downpour&mdash;the heaviest in nearly 40 years&mdash;leaving the city submerged, claiming at least 11 lives, and severely affecting daily life just days before Durga Puja festivities.
ThIndia ia Meteorological Department (IMD) reported that rainfall occurred at a rate of 98 mm per hour, just below the 100 mm mark that defines a cloudburst. 
In a span of six hours, entire neighborhoods were flooded, rail, road, and air traffic came to a halt, and countless homes and apartments were inundated.
In total, Kolkata received 251.4 mm of rain in less than 24 hours, marking the highest single-day rainfall since 1986 and the sixth-highest in the city&rsquo;s 137-year recorded history. 
Rainfall distribution varied across the city, with Garia in the south experiencing 332 mm, while Thanthania in the north received 195 mm.
The floods transformed major thoroughfares into rivers, disrupted Metro and local train services, and damaged several Durga Puja pandals. 
The episode also highlighted the city&rsquo;s vulnerable drainage system, which struggled to handle the massive influx of water.

Kolkata streets submerged, people wade through water

Overnight deluge kills 11, floods city, disrupts Durga Puja prep in Kolkata

Kolkata Flooded By Heaviest Rain In Decades

Overnight deluge kills 11, floods city, disrupts Durga Puja prep in Kolkata

September 24, 2025 | 09:50 IST