A 'red alert' has been issued for today and tomorrow for Chennai and 19 other districts across Tamil Nadu as a low-pressure area over the Bay of Bengal has intensified into a depression, according to the meteorological department.

Heavy rain ranging between 150 and 200 mm is expected in Chennai from this afternoon,

The depression is expected to move west-northwest and hit Tamil Nadu's northern coast, leading to heavy to very rainfall over parts of the southern state as well as neighbouring Puducherry and Karaikal.

The Tamil Nadu government has set up 434 'siren towers' to sound the alert on floods and other emergencies, and is working with telecom networks to ensure mobile connectivity is not affected; 50 cellular phone towers on wheels are ready for use.

Greater Chennai Commissioner Gagandeep Singh Bedi said on NDTV today that as much as 150 to 200 mm rainfall is expected in Chennai and over 50 boats are ready to be deployed for emergency use as fresh floods are expected in the wake of the downpour.

Over 500 motors for pumping out water and 60 heavy duty pumps have been put in place in the traditional low-lying areas which are expected to get inundated due to the heavy rainfall.

Measures to distribute food, electricity generating sets and meet other infrastructure needs are also in place, Bedi and Chennai deputy commissioner G. Sneha said.

The Madras High Court had on Tuesday taken the Greater Chennai Corporation to task for failing to take adequate steps to prevent flooding in the city due to rain.

The High Court has warned the civic body that it would initiate suo motu action if the present situation was not brought under control. It came down heavily on the civic authorities for not doing enough on the issue over the last six years despite the devastating experience of the 2015 floods in city.

Chennai and several suburbs in Chengelpet, Kancheepuram and Tiruvallur districts have witnessed heavy rainfall since Saturday, turning out to be one of the heaviest in recent years. Most roads and bylanes were flooded and neighbourhoods went without power supply.

Five people have died due to rain-related incidents in Tamil Nadu as homes were damaged.

The rainfall recorded in Tamil Nadu is over 43 per cent above normal since the northeast monsoon started last month.

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