India: Southwest Monsoon ends, northeast monsoon begins; Chennai on red alert, IMD warns

Tuesday (Oct 15) marked the withdrawal of the southwest monsoon and simultaneously, the northeast monsoon commenced, said the Indian Meteorological Department (IMD). Coinciding with the onset of the northeast monsoon, there is a weather system intensifying in the Bay of Bengal, which has been bringing intense spells of rain over the southern Indian city of Chennai and adjoining districts. 

The low-pressure area concentrated into a well-marked low-pressure area over the central part of the south Bay of Bengal on Tuesday. It is likely to move northwestwards and intensify into a depression during the next 24 hours, said the IMD. It is likely to continue to move towards north Tamil Nadu, Puducherry and south Andhra Pradesh, the IMD cautioned. 

Owing to this evolving weather system, a red alert for heavy to extremely heavy rainfall has been issued for Chennai and its adjoining districts, for both Tuesday and Wednesday. As per the IMD’s classification, heavy rainfall amounts to 6.4-11.5 cm of downpour in 24 hours, whereas very heavy rainfall amounts to 11.5 cm to 20.4 cm in 24 hours. In case of extremely heavy rainfall, it is more than 20.4 cm in 24 hours. 

Nearly 18 districts across Tamil Nadu would be receiving rainfall of varying intensity, as per the forecast. Throughout the week, winds would be blowing at an average of 50kmph along the Tamil Nadu coast, owing to which fishermen have been urged not to venture into the sea, and those at sea have been asked to return ashore. 

Around 13 teams of the National Disaster Response Force (NDRF), comprising a total of 390 personnel are on standby at Arakkonam, near Chennai. NDRF teams are working in close coordination with the state authorities to render assistance at the required time and place.

Each of these NDRF teams is prepared with rubber boats, tree-cutting chainsaws, communications equipment, ropes and harnesses and first aid kits. The NDRF has also set up a round-the-clock control room at 04 Battalion Arakkonam, near Chennai, to closely monitor the situation. 

In the review meeting chaired by the chief minister, it was ordered that those in flood-prone and vulnerable areas be moved to relief camps, bread, drinking water and other essentials be stocked at the camps, and levels of water bodies be constantly monitored. 

The Tamil Nadu government declared a holiday for schools and colleges in Chennai and adjoining districts for Tuesday. The state government also recommended work from home (WFH) for IT firms from October 15 to 18, considering the weather system that is brewing in the Bay of Bengal.