Now is a good time to assess three decades of progress since Jim Wilson and Ed Brandes summarized the operational capability of radar to provide quantitative rainfall estimates with potential applications to hydrology. , and it was a comprehensive attempt to summarize the capabilities of weather radar to provide quantitative estimates of precipitation, which inspired a generation of radar hydrometeorologists in the United States and elsewhere. They discussed the numerous sources of uncertainties associated with radar-based rainfall estimates, including calibration, attenuation, bright band, anomalous propagation, beam blockage, ground clutter and spurious returns, random errors, and variability in the relation between reflectivity Z and rainfall rate R (Z-R relations). The authors also addressed the possible impact of the errors in rain gauge measurements of rainfall and sampling uncertainties (errors resulting from the approximation of an areal estimate using a point measurement). In particular, based on contemporary research (e.g., Huff 1970;Woodley et al. 1975) concerning the spatial sampling error, Wilson and Brandes (1979) reported that it "decreases with increasing area size, increasing time period, increasing gage density, and increasing rainfall amount." Based on more recent research, we have developed quantitative models that reflect how the spatial sampling errors decrease with increasing temporal and decreasing spatial scales, rain gauge network density, and rainfall amount (e.g., Ciach and Krajewski 1999;Zhang et al. 2007;Villarini et al. 2008;Villarini and Krajewski 2008).These uncertainties notwithstanding, Wilson and Brandes foresaw the operational utility of radarrainfall estimation and promoted its use in flash flood forecasting, noting that "radar can be of lifesaving usefulness by alerting forecasters to the potential for flash flooding."In this article, rather than trying to review the (sizable) literature of the different methods of radarrainfall estimation and their accompanying sources of uncertainties, our goal is to answer the question, How much better can we do now versus what was done 30 yr ago? To answer this question, we replicate,