CHENNAI: Tamil Nadu and Puducherry experienced a notably rainy year in 2025, with the annual monsoon delivering 12 per cent more rain than average, according to the Indian Meteorological Department (IMD).

The region received 1,027.7 mm of rainfall against a long-term normal of 930.9 mm, placing the year in the "normal to excess" category for most districts.

The rainfall pattern, however, was a story of sharp contrasts. The year began with a dry February, marked by isolated showers and patches of dense fog, but shifted dramatically by May, which saw more than double its usual rainfall. The monsoon months brought significant events, including a cloudburst over Manali in late August and an exceptionally active October.

That month was shaped by Severe Cyclonic Storm Montha, which drenched the region and helped push monthly totals well above normal, with the ghat areas of Tirunelveli district recording a remarkable 105 cm.
Cyclonic storm Ditwah is active over the Bay of Bengal from November 26 to December 3. In November, despite Cyclone Ditwath, the month received normal rain with 149.2 mm against the normal of 181.7 mm. Oothu, the ghat areas of Tirunelveli district received 149 cm of rainfall.

This wet trend was not universal. July and December both closed with deficits, and the Chengalpattu district was the sole area to record a deficit for the entire year. Most other districts fared well, with over 25, including Chennai, Kancheepuram, and Puducherry, receiving normal rainfall. Ten districts, such as Coimbatore and Vellore, saw excess rain, while Tirunelveli alone registered a large excess.

Interspersed with the heavy rains were periods of intense heat. From March through September, temperatures consistently soared above 40°C, with Vellore (March 21) and Madurai airport (July 13) both hitting a peak of 41.5°C.

In summary, 2025 was a year of weather extremes for the region-characterised by overall abundant and sometimes intense rainfall, but punctuated by rising mercury and a few dry spells.