27-05-2025
TNAU releases district-level rainfall forecast for Southwest monsoon
Tamil Nadu Agricultural University (TNAU), Coimbatore, on Tuesday released the district-level seasonal rainfall forecast for Southwest Monsoon season, 2025 (June to September).
The rainfall forecast was calculated based on the Southern Oscillation Index and Sea Surface Temperature values of Pacific and Indian Oceans by using Australian Rainman International V.4.3. software at the university's Agro Climate Research Centre.
The TNAU presented its forecast at 60% probability level. Normal rainfall (±10 per cent deviation from long term rainfall) is expected in most of the districts in Tamil Nadu. Near normal rainfall (-10 per cent deviation from the long-term rainfall) is expected in Coimbatore, Tiruppur, Karur, Namakkal, Thenkasi, Tirunelveli, Tutucorin and Kanyakumari districts of Tamil Nadu.
The predicted rainfall (in mm) have been grouped under different zones.
North Eastern Zone (Normal rainfall in mm, predicted rainfall, and percent deviation in brackets): Chennai (440, 430, -2), Chengalpattu (450, 450, 0), Cuddalore (360, 370, 3), Kallakurichi (410, 385, -6), Kancheepuram (479, 462, -4), Ranipet (450, 430, -4), Tiruvallur (456, 440, -4), Tirupathur (416, 400, -4), Tiruvannamalai (449, 449, 1), Villpuram (405, 405, -5), Vellore (453, 422, -7).
West zone: Coimbatore (210, 185, -12), Erode (260, 245, -6), Tiruppur (151, 130, -14).
North West zone: Dharmapuri (392, 380, -3), Krishnagiri (375, 377, 1), Namakkal (336, 300, -11), Salem (421, 410, -3).
Cauvery Delta zone: Ariyalur (377, 355, -6), Karur (199, 175, -12), Mayiladuthurai (295, 300, 2), Nagapattinam (279, 267, -4), Perambalur (279, 269, -4), Thanjavur (314, 315, 0), Tiruvarur (302, 280, -7), Tiruchirapalli (277, 260, -6).
Southern Zone: Dindigul (308, 296, -4), Madurai (325, 298, -8), Pudukkottai (330, 326, -1), Ramanathapuram (135, 135, 0), Sivaganga (417, 421, 1), Theni (215, 205, -5), Tenkasi (174, 150, -14), Tuticorn (67, 59, -12), Tirunelveli (128, 108, -16), Virudhunagar (190, 175, -8).
Hilly Zone: The Nilgiris (875, 860, -2).
