Volcanic debris flow disaster is highly triggered by rainfall. However, limited access to the area of active volcano slope and damage of the observation station restricts the direct measurement by rain gauges. High-resolution X-band weather radars have been extensively used in hydrological researches and flood mitigation programs. In this study, the potential utilization of X-band multi-parameter compact (X-MP) radar for volcanic disaster mitigation is in real-time is presented. The study area

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... s the rivers on Mount Merapi, which is historically the most active volcano in Indonesia. In the first part, the use of X-MP radar in real-time scheme is described. This part demonstrates the radar-rainfall estimation and the first attempt to predict the rain echo motion in short-term by using extrapolation model. In the second part, the advantage of radar for showing the spatially predominant rainfall for vulnerability assessment is demonstrated. The susceptibility level of three river basins, Pabelan River, Boyong River, and Gendol River, is generated using radarrainfall spatial distribution intensive observation period between October 2015 and February 2016. The real-time analysis has shown the advantage of radar to observe short-localized rainfall event. The results of radar extrapolation model suggest the consideration of uncertainties in the prediction system. The susceptibility score calculated from frequency of rainfall threshold exceedance and slope calculated by parametric modeling technique can be used to determine the susceptible area. The analysis finds that generally Boyong River is the most prone area for lahar flow, particularly at the region within 2 km to 3 km from the summit. The proposed X-MP radar utilization would be useful for mitigation of multimodal sediment disaster caused by volcanic eruption.