Climate change driven by global warming is causing frequent large-scale floods, not only in Japan, but across the globe. This situation means that disaster risk reduction measures in Japan have reached a major turning point. The field is about to enter a more practical, advanced phase of efforts to respond to meteorological disasters in the form of typhoons, linear rainbands, and the localized downpours of torrential rain over a short period–known as guerrilla rainstorms. In addition to more accurate forecasting, these responses include flood control plans based on the assumption of flooding. At the same time, appropriate risk communication that conveys uncertainties is also required.