Enhanced polarimetric radar signatures above the melting level in a supercell storm

摘要

The dataset analyzed is the first simultaneous in-situ and radar survey of phenomena associated with observed "columns" of differential reflectivity Z/sub dr/ and specific differential phase K/sub dp/ in a supercell storm. Further, no in situ measurements in regions of such enhanced Z/sub dr/ and K/sub dp/ have ever been reported. The measurements were made in an Oklahoma convective storm that formed in Kingfisher County, on May 17, 1995. Parcel and environmental freezing temperatures were near the 600 mb level (3.5 km AGL). Official observations of 2.5 cm hail were reported as well as a 40 m s/sup -1/ wind gust. Dual-polarization radar measurements were obtained with the NSSL's Cimarron radar. The in situ measurements are provided by the T-28 aircraft at a height of between 4.9 and 5.2 km (near 500 mb; about -5/spl deg/ C). These include temperature, vertical velocity and liquid water content (LWC), as well as hydrometeor size and concentration from the hail spectrometer and a foil impactor.