A low-pressure system over the North Andaman Sea is expected to intensify into a deep depression by September 22, bringing increased rainfall, thunderstorms and gusty winds to Kolkata and parts of south Bengal from September 23 to 26, the Regional Meteorological Centre said, while cautioning that it is still too early to predict whether the system will become a cyclone.
The system developed from an upper-air circulation over the North Andaman Sea on Saturday evening. According to a bulletin issued by the Regional Meteorological Centre, it is very likely to move west-northwestwards and intensify into a depression over the east-central Bay of Bengal on September 21. It is then expected to become a deep depression over the west-central Bay of Bengal on September 22.
The bulletin said the system would continue moving west-northwestwards and is very likely to reach the west-central and adjoining northwest Bay of Bengal, near the south Odisha-north Andhra Pradesh coasts, around the morning of September 23.
Sourish Bandopadhyay, a weather scientist at the Regional Meteorological Centre, said the system was expected to develop into a deep depression with wind speeds of at least 60 kmph. He said the system would be close to cyclone intensity, but added that a cyclone could not yet be predicted with certainty.
Kolkata may receive sporadic and localised rain on Sunday and Monday as the system moves closer to the coast. The weather office said the increased moisture flow associated with the system would lead to cloud formation and heavier rain, particularly in coastal districts of Bengal, with Kolkata also likely to be affected.
Thunderstorms and gusty winds, along with heavy rainfall at some locations, have been forecast across south Bengal between September 23 and 26. The forecast comes after Kolkata remained dry and humid on Saturday, before the developing system began strengthening over the Bay of Bengal.
The Regional Meteorological Centre is continuing to track the system’s movement and intensification. Further forecasts will determine the extent of rainfall and wind impacts in Kolkata, coastal Bengal and neighbouring areas as the system approaches the coast.
