Rainfall Probability Analysis for Strategic and Efficient Crop Planning in Namakkal district, Tamil Nadu

The study mainly intended to understand the rainfall probability of rainfed agricultural region for crop planning. Rainfall is the important climatic variable in rainfed farming. Probabilities of occurrence of rainfall in an area will provide adequate knowledge to the farmers to make tactical farm level decisions for profitable crop production. The study area is the water scarce Namakkal district of Tamil Nadu. The study carried out with the base of secondary data. Weibull’s method of probability is used in the analysis. Probabilities have been worked out for annual and seasonal time slices for each rainfall location present in the study area. 80% probability has been taken as assured rainfall. The result indicates that for Namakkal, at 80% probability level 632.7mm of rainfall is assured annually. The results are tabulated as well shown cartographically using Arc GIS.