For this study, the primary objective is to characterize TDS's that are associated with weaker tornadoes (EF-0, EF-1, and some low end EF-2's) that form in a Quasi-Linear Convective System (QLCS) environment. Characteristics of QLCS TDS's (e.g., size or areal extent, height, duration, etc.) are compared to supercell TDS's. By understanding the differences and similarities of TDS's in the two storm modes, researchers, forecasters, and warning coordination personnel will be able to improve the utility of TDS's in operational settings.
Data from the Advanced Radar for Meteorological and Operational Research, ARMOR (C-band), and several National Weather Service Weather Surveillance Radars - 1988 Doppler, WSR-88D's (S-band), were collected and utilized for this study. Numerous polarimetric variables were recorded for each TDS which include: ZHH, VR, ρHV, ZDR, and spectrum width (σ). The maximum and minimum values for each variable are recorded to investigate potential refinements to the TDS thresholds for operational forecasters to utilize in QLCS situations. Preliminary results show that the TDS's associated with QLCS tornadoes generally last one, but no more than two volume scans, and rarely are higher than a few thousand feet.