Monthly rainfall forecast in Nakhon Phanom province at the station Lower Nam Kam Project

Abstract

This research aimed to study the monthly rainfall in Nakhon Phanom Province collected from the Monthly Rainfall Survey Station of the Lower Nam Kam Project, That Phanom District, Nakhon Phanom Province. The objective of this research was to find a suitable forecast technique for monthly rainfall and to compare the error values ​​of two statistical forecast methods: the Box-Jenkins method; and a simple seasonal exponential smoothing method. This is based on the lowest mean absolute percent error (MAPE) and root mean square error (RMSE) from 2009 to 2018. Then, forecast monthly rainfall in advance in 2019 by create a 9-year forecast model to be used as the data for the comparison of the forecast model. The results showed that the Box-Jenkins method of rainfall forecast It is more suitable than the simple seasonal exponential smoothing method. MAPE and RMSE were the lowest based on the forecast from January to December 2019.