Tamil Nadu records excess rainfall in 2024; Chennai city's run continues for 5th year

CHENNAI: The northeast monsoon has come to an end on Tuesday after recording 33 per cent excess rain with 590 mm of rainfall from October to December. The withdrawal of the monsoon is likely to be announced after January 15, said weather officials.

With 1,179 mm of rainfall in 2024, Tamil Nadu has recorded excess spells throughout the year, with no district recording deficit rainfall, unlike the previous years. Tirunelveli topped the list with 100 per cent increase. Chennai, too, had a beneficial year, continuing the run for the fifth consecutive year.

"The easterly wind was more active in the State in 2024, which was one of the reasons for the above-average rainfall. Even though only four cyclones were formed compared to six during the monsoon seasons in the previous year, we received excess rainfall under the influence of low-pressure areas and depressions prevailed over the sea. During the northeast and southwest monsoons, Tamil Nadu recorded 33 per cent and 18 per cent excess rainfall, respectively, whereas the overall rainfall has increased by 28 per cent," said S Balachandran, Deputy Director-General of Meteorology, Regional Meteorological Centre (RMC), Chennai.

Overall, Tirunelveli recorded double as that of normal rainfall, while 26 other districts witnessed above-average rainfall. In the remaining 12 districts, the rainfall received was categorised as ‘average’.

During the northeast monsoon, Tirunelveli, Salem, Dharmapuri, Krishnagiri, Tirupattur, and Villupuram recorded large excess, 23 districts excess, and 11 districts average rainfall.

During the southwest monsoon (July to September), Tirunelveli received 268 per cent above normal, and 16 and 7 districts with above average and average rainfall, respectively. Six districts recorded deficit rainfall during the season.

Compared to 2023, the rainfall received in Tamil Nadu has increased by 15 per cent. Also, the monsoon spells have increased by 10 per cent and 27 per cent in SWM and NEM respectively.

"The State has witnessed 15th best overall rainfall in 2024 from 1871 and the capital city has received excess rainfall for the fifth consecutive year during the monsoon season. In 2023, several interior districts recorded deficit rainfall. However, this year only Thoothukudi (-8%) and Nilgiris (-1%) witnessed lesser rainfall than normal," said K Srikanth, a city-based independent weather blogger.

This stands in stark contrast with 2016 when the monsoon failed, while it was below average in 2017. However, Tamil Nadu has been receiving excess rainfall during the monsoon seasons since 2020. "Even though the State received intense rainfall from October to December, there were more dry spell days, too; we cannot directly attribute climate change as the reason. We had intense rainfall to compensate for the dry days," he added.

Another blogger Pradeep John, popularly known as Tamil Nadu weatherman, said it is not often that the northeast monsoon brought in excess rainfall to Chennai for five consecutive years.

He noted that there was such a great streak for seven years from 2005 to 2011. The uniqueness of the season this year was that the rains were spread over all three months without any extreme spells like 2023. “This year we got major spells in mid-October, [Cyclone] Fengal in November end, and the December second-week rains. The three spells were in the 150 mm range," he said on social media.

Usually in Tamil Nadu, the maximum temperature would reduce in January and February. However, several districts witnessed mist/haze during the early morning hours in December itself. Chennai, too, reported a drop in the maximum temperature a few days.

"As there was intense rainfall on most days, the winter has increased to 113 per cent. In 2023, the winter saw a drop by 17 per cent," said Balachandran, noting that such situations prevail during the monsoon seasons, especially when there is heavy rainfall.

Meanwhile, rainfall activity is vigorous over south Tamil Nadu, where it is predicted to continue till January 15. Hence, the withdrawal of the monsoon is likely to be announced after that. In 2023, the NEM commenced on October 21 and ended on January 15, 2024.