An Evaluation of Relationships between Radar-Inferred Kinematic and Microphysical Parameters and Lightning Flash Rates in Alabama Storms

Abstract

Lightning flash rate parameterizations based on polarimetric and multi-Doppler radar inferred microphysical (e.g., graupel volume, graupel mass, 35 dBZ volume) and kinematic (e.g., updraft volume, maximum updraft velocity) parameters have important applications in atmospheric science. Although past studies have established relations between flash rate and storm parameters, their expected performance in a variety of storm and flash rate conditions is uncertain due to sample limitations. Radar network and lightning mapping array observations over Alabama of a large and diverse sample of 33 storms are input to hydrometeor identification, vertical velocity retrieval and flash rate algorithms to develop and test flash rate relations. When applied to this sample, prior flash rate linear relations result in larger errors overall, including often much larger bias (both over- and under-estimation) and root mean square errors compared to the new linear relations. At low flash rates, the new flash rate relations based on kinematic parameters have larger errors compared to those based on microphysical ones. Sensitivity of error to the functional form (e.g., zero or non-zero intercept) is also tested. When considering all factors (e.g., low errors including at low flash rate, consistency with past linear relations, and insensitivity to functional form), the flash rate parameterization based on graupel volume has the best overall performance.

Observations of Anomalous Charge Structures in Supercell Thunderstorms in the Southeastern United States

“…Beyond advancing understanding of the physical origins of charge structure, the development of ACS characterization carries implications for remote sensing and nowcasting of thunderstorms. Lightning data are increasingly utilized for severe storm nowcasting because of intrinsic relationships between lightning, thunderstorm intensity, and production of high‐impact convective phenomena (e.g., Carey et al, 2019; Deierling & Petersen, 2008; Lang & Rutledge, 2002; MacGorman et al, 1989; Reap & MacGorman, 1989; Schultz et al, 2011, 2015; Schultz et al, 2017; Stough et al, 2017; Williams et al, 1999). Anomalous storms are often associated with increased severe weather production, including increased quantities of and/or larger severe hail (e.g., Branick & Doswell III, 1992; Carey & Rutledge, 1998; Curran & Rust, 1992; Gilmore & Wicker, 2002; Lang & Rutledge, 2002; MacGorman & Nielsen, 1991; MacGorman & Burgess, 1994; Reap & MacGorman, 1989; Seimon, 1993; Stolzenburg, 1994).…”

Impulsive Volcanic Plumes Generate Volcanic Lightning and Vent Discharges: A Statistical Analysis of Sakurajima Volcano in 2015

“…Ice generation in high altitude plumes also contributes to charge generation in a process believed to be analogous with thunderstorm charging (e.g. Calbuco, Van Eaton et al, 2016;Bogoslof, Van Eaton et al, 2020;Anak Krakatau, Prata et al, 2019, meteorological thunderstorms, Williams andMcNutt, 2005;Carey et al, 2019). Yet, at the lower plume heights common at Sakurajima (<5 km), plume…”

Distinctive Signals in 1‐min Observations of Overshooting Tops and Lightning Activity in a Severe Supercell Thunderstorm

“…In particular, this set of observations could revolutionize convection studies in SESA given the clear improvement that it represents to the previously available 10‐ or 15‐min resolution satellite information in the region. Recent studies have analyzed the advantages of super rapid scan operations for GOES and high‐temporal lightning observations from ground‐based LMAs (Apke et al, 2018; Bedka et al, 2015; Carey et al, 2019; Mecikalski et al, 2016; Ribeiro et al, 2019). Since most physical processes involved throughout the life cycle of severe weather are fast‐evolving, it is clear that nowcasting algorithms based on the previously available satellite observations can be improved with state‐of‐the‐art satellite observations.…”