AbstractAtmospheric rivers (ARs) account for more than 90% of the total meridional water vapor flux in midlatitudes, and 25â50% of the annual precipitation in the coastal western United States. In this study, reflectivity profiles from the Global Precipitation Measurement DualâFrequency Precipitation Radar (GPMâDPR) are used to evaluate precipitation and temperature characteristics of ARs over the western coast of North America and the eastern North Pacific Ocean. Evaluation of GPMâDPR brightâband height using a network of groundâbased vertically pointing radars along the West Coast demonstrated exceptional agreement, and comparison with freezing level height from reanalyses over the eastern North Pacific Ocean also consistently agreed, indicating that GPMâDPR can be used to independently validate freezing level in models. However, precipitation comparison with gridded observations across the western United States indicated deficiencies in GPMâDPR's ability to reproduce the spatial distribution of winter precipitation, likely related to sampling frequency. Over the geographically homogeneous oceanic portion of the domain, sampling frequency was not problematic, and significant differences in the frequency and intensity of precipitation between GPMâDPR and reanalyses highlighted biases in both satelliteâobserved and modeled AR precipitation. Reanalyses precipitation rates below the minimum sensitivity of GPMâDPR accounted for a 20% increase in total precipitation, and 25% of radarâderived precipitation rates were greater than the 99th percentile precipitation rate in reanalyses. Due to differences in the proportions of precipitation in convective, stratiform brightâband, and nonâbrightâband conditions, AR conditions contributed nearly 10% more to total precipitation in GPMâDPR than reanalyses.