This study proposes a runoff forecasting method that considers snowmelt in addition to rainfall, which will remain applicable throughout the year in snowy and cold regions. Climate change has complicated considering heavy rainfall combined with snowmelt and not many studies and practical examples of runoff models that account for snowmelt exist. In this study, we propose a distributed runoff modeling method that consists of snowmelt estimation, slope runoff considering snow cover, and river channel tracking. This method enables estimation of the amount of snowmelt, without the need for snow accumulation models by using the snow depth analysis of JMA. We first confirmed the validity of the water balance using long-term slope runoff calculations and used past cases to perform predictive calculations. The results indicate that accurate calculations are possible for both the snowmelt season and the summer season, demonstrating that it is possible to use public meteorological information to calculate highly practical runoff predictions that can be applied to drainage basins including snowy and cold regions throughout the year.