Heavy Rainfall Expected as Cyclonic System Develops Over Bay of Bengal

KalimNews, May 27, 2025, Kolkata : The India Meteorological Department (IMD) has announced the formation of a low-pressure area over the northwest Bay of Bengal, off the Odisha coast, under the influence of a cyclonic circulation. The system, associated with a cyclonic circulation extending up to 7.6 km above mean sea level, is expected to move slowly northwards and strengthen over the next 48 hours. This development is likely to bring significant weather changes across several regions of India, with isolated places expected to receive heavy rainfall.

A cyclonic circulation over the west-central Bay of Bengal is intensifying into a low-pressure system, which the IMD expects to strengthen further. This system is being influenced by a trough extending from Marathwada to the northeast Bay of Bengal, located about one kilometer above mean sea level. The system is drawing moist winds from the southeast into southern West Bengal, resulting in consistent rainfall across the region.

The IMD has warned of heavy to very heavy rainfall in West Bengal throughout the week, with the potential for extremely heavy rain on Thursday and Friday. Cloudy skies, moderate rain, and lightning are expected in Kolkata and surrounding areas, with temperatures hovering between 32°C and 26°C. The southwest monsoon is advancing under favorable conditions and is expected to reach sub-Himalayan West Bengal and Sikkim within the next three days, having already covered parts of northeastern India, including Assam and Meghalaya.

In West Bengal, districts such as North and South 24 Parganas, East and West Midnapore, Jhargram, Kolkata, Howrah, Hooghly, Bankura, and West Burdwan are forecast to experience heavy rainfall on Thursday. On Friday, very heavy to extremely heavy rainfall is predicted for East and West Burdwan, East and West Midnapore, Bankura, Birbhum, and Hooghly, with some areas potentially receiving up to 200 mm of rainfall.

In north Bengal, while light to moderate rain is expected on Tuesday and Wednesday, heavy to extremely heavy rainfall is anticipated from Thursday onward. The districts of Darjeeling, Kalimpong, Alipurduar, Cooch Behar, and Jalpaiguri are expected to witness intense downpours through the weekend, with some areas receiving up to 200 mm of rainfall. Malda and North and South Dinajpur are also likely to experience heavy rainfall.

Despite brief periods of relief from thunderstorms, Kolkata's high humidity, ranging from 77 percent to 97 percent on Tuesday, is expected to continue, making the weather uncomfortable during dry spells. The recorded high temperature was 31.3°C, with a low of 25.8°C, and rain activity is expected to intensify starting Wednesday.

Meanwhile, the IMD forecasts that areas in North Coastal Andhra (NCAP), Yanam, South Coastal Andhra Pradesh (SCAP), and Rayalaseema will experience heavy rainfall, accompanied by thunderstorms and lightning at isolated locations. Gusty winds with speeds reaching 50-60 km/h are expected over SCAP and Rayalaseema, while wind speeds of 40-50 km/h are anticipated in NCAP and Yanam. These weather conditions are likely to persist for the next three days.

Additionally, the IMD has indicated that the Southwest Monsoon is expected to advance further into Andhra Pradesh over the next two to three days, with conditions becoming favorable for its progress. The forecast for specific districts in Coastal Andhra includes heavy rainfall on Wednesday, particularly in the districts of Alluri Sitarama Raju, East Godavari, Palnadu, and Eluru, along with Yanam. By Thursday, rainfall is expected to intensify, with heavy rain likely in areas such as Srikakulam, Parvathipuram Manyam, Kakinada, and NTR districts.

Several areas in Andhra Pradesh have already recorded considerable rainfall, with Pamulavaka in Anakapalli district receiving the highest at 46.5 mm. Other locations, such as Narsingapalli (41.2 mm), Yelamanchili (40.7 mm), and Anakapalli town (29 mm), also saw substantial rainfall on Tuesday. According to the IMD's latest update, above-normal rainfall is expected in Andhra Pradesh during the 2025 monsoon season.

Due to the developing low-pressure system, sea conditions are expected to be rough. Fishermen have been advised not to venture into the deep seas of the north and central Bay of Bengal from May 28 to Saturday, with similar warnings issued for the coasts of West Bengal and Odisha.