
Normal Rainfall (+19% from mean seasonal rainfall) is expected in Ariyalur, Chennai, Cuddalore, Dindigul, Dharmapuri, Erode, Karur, Kancheepuram, Kanyakumari, Krishnagiri, Madurai, Namakkal, Perambalur, Pudukottai, Salem, Sivagangai, Thanjavur, Theni, Tirunelveli, Tuticorin, Tiruchirappalli, Nilgiris, Tiruppur, Tiruvallur, Tiruvannamalai, Villupuram, Vellore and Virudhunagar.
Deficit Rainfall (-19 per cent to -59% from mean seasonal rainfall) is expected in Coimbatore, Nagapattinam, Ramanathapuram and Tiruvarur districts, according to a data released by Tamil Nadu Agricultural University (TNAU).
Tamil Nadu is a rain shadow area to South West Monsoon, nearly 32 per cent of the total annual rainfall of the state is received from this monsoon, Director of Crop Management C Jeyanthi and Professor and Head, Agro Climate Research Centre, TNAU, S Paneerselvam told reporters.
Farmers of Dharmapuri, Krishnagiri, Salem, Nilgiris and Kanyakumari are benefited from this seasonal rainfall to take up strategic farm decisions, they said.
District level rainfall forecast for the Southwest monsoon over Tamil Nadu was developed at the Centre, based on the Southern Oscillation Index of summer season and Sea Surface Temperature values of Pacific and Indian Oceans using Australian Rainman International V.4.3.Software, Jeyanthi said.
The historical rainfall data collected from Tamil Nadu Agricultural University Stations were used to represent the district rainfall information.
In the absence of data from research station in a particular district, data from Rainman software were used, they added.