Observations of severe convective storms with operational dual-polarization WSR-88D radars

The upgrade of the U.S. National Weather Service WSR-88D radar network to dual-polarization capabilities is underway. By the time of the conference, well over half of the 160 radars will have been upgraded, covering many different climatological regions of the United States. Many of these radars were operational during severe convective weather events, providing forecasters with real-time polarimetric data to aid in the warning decision process.

Examples of polarimetric radar signatures in a variety of severe convective storms from across the United States will be presented. These include supercell signatures such as the Z_DR arc in both left- and right-moving supercells, tornadic debris signatures, Z_DR columns, signatures of large and giant (> 2 in or 5 cm) hail, polarimetric three-body scattering, low-level inflow, anomalously large differential attenuation, and depolarization streaks. Explanations and physical interpretations of these signatures will be provided. The operational benefits and limitations of these various signatures will also be discussed.