Sixty five per cent of Tamil Nadu would receive normal rainfall during the South West monsoon, Tamil Nadu Agricultural University said here today. Tamil Nadu is a rain shadow area to South West Monsoon and nearly 32 per cent of the state’s total annual rainfall is received from this monsoon, which today hit Kerala and the Northeast, two days ahead of its scheduled arrival. TNAU’s Agro Climatic Research Centre in its forecast said Salem, Namakkal, Dharmapuri, Krishnagiri, and Nilgiris districts are expected to receive normal rainfall.
Chennai, Coimbatore, Cuddalore, Dindigul, Erode, Kancheepuram, Kanyakumari, Madurai, Perambalur, Pudukottai, Sivagangai, Theni, Tiruvallur, Tiruvannamalai, Villupurum and Vellore districts are also expected to receive normal rainfall during the Monsoon, it said. Deficit rainfall is expected in Nagapattinam, Ramanathapuram, Tirunelveli, Tutucorin, Tiruppur, Karur, Virudhunagar, Tiruchirappali, Thanjavur, Ariyalur and Tiruvarur districts, the release said.
TNAU advised deficit rainfall districts to follow normal cropping pattern with existing agro-technologies along with weather based agro advisories in normal rainfall districts. They should use the forecast to make strategic decisions to raise short duration, less water requiring crops with available irrigation facilities, it said. TNAU said that district level rainfall forecast for June to September was developed based on Southern Oscillation Index of summer season and Sea Surface Temperature values of east pacific ocean using Australian Rainman International V.4.3. software. The historical rainfall data collected from University Stations was used to represent the basis for district rainfall data set, the release said, adding that in the absence of data from research stations in a particular district, data from Rainman software were used alternatively.