The district level rainfall forecast for the North East Monsoon (October to December) 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.
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.