Polarimetric radar measurements made by the recently upgraded CSU-CHILL radar system in a severe hailstorm are analyzed permitting for the first time the combined use of Z h , Z DR , linear depolarization ratio (LDR), K DP , and h to infer hydrometeor types. A chase van equipped for manual collection of hail, and instrumented with a rain gauge, intercepted the storm core for 50 min. The period of golfball-sized hail is easily distinguished by high LDR (greater than or equal to Ϫ18 dB), negative Z DR (less than or equal to Ϫ0.5 dB), and low h (less than or equal to 0.93) values near the surface. Rainfall accumulation over the entire event (about 40 mm) estimated using K DP is in excellent agreement with the rain gauge measurement. Limited dual-Doppler synthesis using the CSU-CHILL and Denver WSR-88D radars permit estimates of the horizontal convergence at altitudes less than 3 km above ground level (AGL) at 1747 and 1812 mountain daylight time (MDT). Locations of peak horizontal convergence at these times are centered on well-defined positive Z DR columns. Vertical sections of multiparameter radar data at 1812 MDT are interpreted in terms of hydrometeor type. In particular, an enhanced LDR ''cap'' area on top of the the positive Z DR column is interpreted as a region of mixed phase with large drops mixed with partially frozen and frozen hydrometeors. A positive K DP column on the the western fringe of the main updraft is inferred to be the result of drops (1-2 mm) shed by wet hailstones. Swaths of large hail at the surface (inferred from LDR signatures) and positive Z DR at 3.5 km AGL suggest that potential frozen drop embryos are favorably located for growth into large hailstones. Thin section analysis of a sample of the large hailstones shows that 30%-40% have frozen drop embryos.

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Direct intercomparisons between space-and ground-based radar measurements can be a challenging task. Differences in viewing aspects between space and earth observations, propagation paths, frequencies, resolution volume size, and time synchronization mismatch between space-and ground-based observations can contribute to direct point-by-point intercomparison errors. This problem is further complicated by geometric distortions induced upon the space-based observations caused by the movements and attitude perturbations of the spacecraft itself. A method to align measurements between these two systems is presented. The method makes use of variable resolution volume matching between the two systems and presents a technique to minimize the effects of potential geometric distortion in space radar observations relative to ground measurements. Applications of the method are shown that make a comparison between the Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR) reflectivity measurements and ground radar.

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