Kolkata, Sep 23 (PTI) A downpour in the dead of night for three hours left large areas of Kolkata submerged under water, with the IMD recording 185.6 mm of rain between 2.30 am and 5.30 am on Tuesday.
The heavy rain was caused by a low-pressure area, and showers are likely to continue in the already wet districts in the southern part of West Bengal till Wednesday morning.
Another similar system is likely to form on September 25 and bring showers to the region, according to the Met office.
On Tuesday, the maximum hourly rainfall of 98 mm was recorded between 3 am and 4 am, the IMD said, clarifying that it does not satisfy the cloudburst criteria.
According to the India Meteorological Department (IMD), rainfall exceeding 100 mm in an hour over a 20 to 30 sq km area is defined as a cloudburst.
The metropolis recorded 48.6 mm rainfall between 11.30 pm on Monday and 2.30 am on Tuesday, while 12.1 mm rainfall was recorded between 5.30 am and 8.30 am, the IMD said.
Kolkata recorded extremely heavy rainfall of 251.4 mm in a 24-hour period till 8.30 am on Tuesday, the Met data said.
The adjoining Salt Lake area recorded 230 mm rainfall during the same 24-hour period, it said.
It said that a low pressure area, which formed on Monday, is situated over the coastal areas of Gangetic West Bengal and adjoining north Odisha and the Bay of Bengal on Tuesday.
The IMD said that another low-pressure area is likely to form over the sea on September 25.
It is very likely to cross south Odisha-north Andhra Pradesh coasts around September 27, the Met said.
In view of these weather systems, widespread light to moderate rainfall with isolated heavy to very heavy rainfall is very likely over some districts of south Bengal.
The Met said that heavy to very heavy downpour (7 to 20 mm) is very likely at one or two places over Purba and Paschim Medinipur, Jhargram and Bankura districts, while heavy rainfall (7 to 11 mm) will occur in Kolkata, South and North 24 Parganas, Howrah, Hooghly and Purulia districts till Wednesday morning.
Light to moderate rainfall is very likely to occur in most of the other places in south Bengal till Saturday, it said.
The IMD advised fishermen not to venture into the sea over north Bay of Bengal and along and off West Bengal-Odisha coasts till Saturday as squally weather with surface wind speed exceeding 45 km per hour is very likely to prevail in the region. PTI AMR NN
