Abstract:
In the present study, statistical and probability analysis of 40 years daily rainfall data for the period 1971-2010
were carried out on weekly, monthly and annual basis. Rainfall pattern in the area is also analyzed using thiessen
polygon and Histogram technique. Probability analysis was done using two and three parameters probability
distribution functions. The best distribution representing the command was identified using Chi-squared (
2) test
at different probability level. Amongst the nine distributions fitted in the Tawa canal command, Log-normal
distribution and Weibull distribution (2) are found as the best fit distribution for annual and monthly rainfall data
respectively. When the distributions depicting standard monsoon and non-monsoon weeks in the region are
studied, it has been found that Beta and Weibull represents best in comparison to other distributions. Finally, the
best fit distribution is employed for computing the minimum assured amount of rainfall at different probability
levels for the command area.
