**1. Introduction**

Drought is a condition when there is very little extreme rainfall or no rainfall for a relatively long period outside the dry season [1, 2]. Its occurrence in a watershed is recommended to be analyzed using discharge data in addition to the rainfall data [3]. Moreover, the hydrological drought index (HDI) is normally used to describe the drought severity based on discharge data which is indicated as HDI1, and simulation which is denoted as HDI2. The discharge prediction model, which is known as the Artificial Neural Network model, is based on a flexible mathematical structure and has the ability to identify a complex nonlinear relationship between input and output [4]. The characters of the rainfall and discharge data were also observed to be adaptable to the method. The purpose of this research is to answer the following questions:

1.What is the estimated discharge calculation model based on rainfall data?

