Probability analysis of 5-day antecedent rainfall at different return periods and seasons for Doimukh (Itanagar), Arunachal Pradesh

Daily rainfall data recorded at Doimukh station for a period of 26 years (1988–2013) were used in this analysis. The 5 days total antecedent rainfall prior to the storm was calculated under three different seasons, i.e. pre-monsoon (March to May), monsoon (June to October) and post-monsoon (November to February). The 5 days antecedent rainfall was classified into AMC-I, AMC-II and AMC-III groups for all the seasons. Four probability distributions were fitted to 5 days antecedent rainfall data for different groups and 5 days antecedent rainfall at 1 to 100 years return period were calculated for the study site.