Application of ARIMA models in forecasting average monthly rainfall in Birzeit, Palestine

Abstract

Town of Birzeit is located on top mountains of the district of Ramallah and Al-Bireh, Palestine. Its elevation is about 800 meters above sea level and enjoys Mediterranean climate. The whole West Bank of Palestine in general and Birzeit in specific suffers from lack of water supplies especially in summer. It becomes necessary to analyze the present rainfall pattern and to predict its future pattern too since it has not been tackled before. In this study authors have reported the Box-Jenkins ARIMA methodology and comparative study of ETS model for rainfall forecasting at Birzeit for the period which extendsfrom September -2003 to August-2021. This study aimed to use two types of rain forecasting models and to select best one. The study concluded that the seasonal ARIMA model (11.0.2) x (11.0.2) is the best in predicting rainfall for the next four years, from September -2021 to August -2025. In Birzeit, rainfall starts in October and gradually increases in December, January and February. However, it starts declining duringmonths of March, April and May.