Expected Withdrawal of Northeast Monsoon in Tamil Nadu After Abundant Rains Starting January 15

Chennai, Jan 1 (NationPress) The weather department is set to officially declare the withdrawal of the northeast monsoon from Tamil Nadu on January 15. This monsoon season, which initiated on October 1, 2024, has delivered substantial rainfall in Tamil Nadu so far.

The northeast monsoon has reported a remarkable 33 percent excess rain, accumulating 590 mm of rainfall between October and December.

Officials indicated that the official announcement regarding the monsoon's withdrawal is anticipated after January 15.

With a total of 1,179 mm of rainfall in 2024, Tamil Nadu has experienced consistent rainfall throughout the year, with no district reporting a deficit, which is a significant change from previous years.

Tirunelveli recorded the highest increase at 100 percent. Chennai also had a favorable year, marking its success for the fifth consecutive year. According to S. Balachandran, the Deputy Director General of Meteorology, the easterly winds were notably more active in the state during 2024, contributing to the above-average rainfall.

Despite only four cyclones forming this year compared to six in the prior monsoon season, Tamil Nadu has still benefited from excess rainfall due to the influence of low-pressure systems and depressions over the sea.

During the northeast and southwest monsoons, Tamil Nadu recorded 33 percent and 18 percent excess rainfall, respectively, leading to an overall increase of 28 percent in rainfall.

The state achieved its 15th best overall rainfall since 1871 in 2024, while the capital city has seen excess rainfall for the fifth consecutive year during the monsoon season.

In contrast, the year 2023 saw several interior districts facing rainfall deficits. This starkly contrasts with the situation in 2016 when the monsoon failed and was below average in 2017.

However, since 2020, Tamil Nadu has consistently received excess rainfall during the monsoon seasons.

The heavy rains that began with the onset of the northeast monsoon (from October 1 onward) have brought the reservoirs in Tamil Nadu close to their full capacity.

Water storage levels in the state’s reservoirs are currently only 12 percent short of their total capacity of 224.297 thousand million cubic feet (TMC).

The Tamil Nadu Water Resources Department (WRD) has reported that 12 reservoirs — three in the Coimbatore region, seven in the Madurai region, and two in the Chennai region — have reached their full capacity.

Moreover, 18 reservoirs have exceeded 90 percent of their total capacity, while 23 reservoirs have water levels ranging from 70 percent to 80 percent.

The Stanley Reservoir at Mettur, the largest in Tamil Nadu, currently holds 97.51 percent of its capacity, equating to 91.146 TMC out of a total capacity of 93.470 TMC. As of Tuesday, the dam recorded an inflow of 7,368 cusecs and discharged 1,300 cusecs downstream.

In addition, the water level of the Sathanur Reservoir stands at 117 feet, just below its full reservoir level (FRL) of 119 feet.

The overall water storage across Tamil Nadu’s reservoirs is at 195.455 TMC, which is 24.824 TMC short of reaching full capacity.

Intense rainfall during the northeast monsoon has significantly boosted water inflows into the state’s 90 reservoirs, elevating storage levels by 10.68 percentage points — from 76.46 percent to 87.14 percent.

Heavy rains in districts such as Tenkasi, Theni, Virudhunagar, Ariyalur, Trichy, Karur, Pudukottai, and Ramanathapuram have further enhanced water storage levels.

The Cyclone Fengal, which affected the region on December 1 and 2, caused unprecedented rainfall in several northern districts, rapidly replenishing tanks and water bodies.

In Tiruvannamalai, 507 out of 697 tanks are now full, along with 359 out of 578 tanks in Tiruvallur, 227 out of 336 tanks in Kallakurichi, and 460 out of 564 tanks in Chengalpattu.

However, floods resulting from the cyclone have damaged numerous tanks and water bodies in northern districts, particularly in Villupuram.

Consequently, water from some tanks had to be released to prevent them from reaching optimal storage levels.