The city received a spell of rain and thunderstorms on Sunday afternoon, bringing down the temperature and easing discomfort.
However, the shower also uprooted trees and snapped branches in several places.
The Alipore Met office recorded 19.3mm of rain in a couple of hours, till 5.30pm.
Thunderstorm and lightning accompanied by rain and gusty wind clocking up to 70kmph in parts of Calcutta, Howrah, Hooghly, North and South 24-Parganas, the Met office said.
Around 4pm, at several places across the city, the sky turned dark and vehicles on the road had to switch on the headlights to navigate.
Five trees were uprooted in Mudiali, Sahapur Road in New Alipore, and Jadavpur, sources in the Kolkata Municipal Corporation (KMC) said.
In some places, branches fell off, too.
“We are expecting light to moderate rain almost everyday now, and temperature will not be very high,” said H.R. Biswas, head of the weather section at the Regional Meteorological Centre at Alipore.
On Sunday, the maximum temperature was 34.6° Celsius, which is 0.6 degrees below normal, and the minimum temperature at 27.5° Celsius was 0.3 degrees above normal.
“Discomfort levels remained high for much of the day, particularly in the morning and later part of the day.
Humidity made the weather unbearable and commuters were seen using umbrellas to protect themselves from the sun.
The southwest monsoon has further advanced into some parts of westcentral and entire northeast Bay of Bengal, some more parts of northwest Bay of Bengal, entire Nagaland, Manipur and Mizoram, parts of Tripura, Assam and Arunachal Pradesh on Sunday, the Met office said.
“We expect the monsoon to enter north Bengal in the next three to four days. It will start with Cooch Behar and then continue to the other upper districts,” said Biswas.
Till late on Sunday, the city civic body was removing the uprooted trees and branches to make way for traffic.
Traffic was affected on a stretch of James Long Sarani after a branch fell and blocked almost the entire road.
“The immediate response is to chop off the branches into smaller pieces and clear the road for traffic,” sources in the civic body said.