This study uses high-resolution ground-based scanning radar observations to investigate precipitation variability across the instantaneous field-of-view (FOV) of satellite-based precipitation radar measurements. This precipitation variability leads to non-uniform beam filling (NUBF) effects in radar measurements, which in turn, impacts satellite-based rainfall estimates produced using measurements collected by the Dual-frequency Precipitation Radar (DPR) on the NASA/JAXA Global Precipitation Measurement (GPM) mission core satellite. By simulating DPR measurements from ground-based scanning radar observations, this study found a linear relationship between precipitation variability of nine 3×3 neighboring FOVs with sub-FOV variability. This result supports using precipitation variability estimated from neighboring FOVs to estimate unresolved sub-FOV variability, or NUBF effects, in satellite-based rainfall retrieval algorithms.