MONTHLY RAINFALL AMOUNT FORECASTING IN KANCHANADIT DISTRICT SURAT THANI PROVINCE BY STATISTICS FORECASTING TECHNIQUES

Abstract

Study the appropriate forecasting mode for the rainfall in Kanchanadit, Surat Thani Province. The data used in this research was the average monthly rainfall from Surat Thani Meteorological Station January 2013 to February 2020 (86 values). The time series data were divided into two categories. The first 74 values from January 2013 until February 2019 were used for the modeling by Decomposition Method, Triple Exponential Smoothing: Winter’s Method, Box – Jenkins Method. The last 12 values from March 2019 to February 2020 were, on the other hand used to check the forecasting models' accuracy via the determination of the Mean Absolute Percentage Error. Research findings indicated that for all the forecasting methods that had been studied, Box – Jenkins Method is the most suitable for this time series, with the forecasting model: