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Christopher J. Schultz, Lawrence D. Carey, Elise V. Schultz, and Richard J. Blakeslee

studies relied on the observed connection between kinematics, microphysics, and electrification within thunderstorms via the noninductive charging mechanism (e.g., Takahashi 1978 ; Saunders et al. 2006 ). Electrification within thunderstorms is found to occur on the order of the quarter- to half-life of an ordinary thunderstorm. 2 Research shows that initial electrification in the primary development of thunderstorms is approximately 10–15 min (e.g., Dye et al. 1986 ; Bringi et al. 1997

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Bongjae Kuk, Hongil Kim, Jongsung Ha, Hyokeun Lee, and Gyuwon Lee

develop a total membership function for lightning (TMF) calculated from fuzzy logic algorithms, and to evaluate the lightning forecasting performance of TMF using skill scores. 2. Data and methodology a. Radio sounding observation data In this study, thermodynamic and kinematic parameters were determined from radio sounding observation data from five sites during 2004–09. The basic information derived from the soundings is summarized in Fig. 1 and Table 1 . Osan and Gwangju, operated by the

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Christopher J. Schultz, Lawrence D. Carey, Elise V. Schultz, and Richard J. Blakeslee

size and/or magnitude for a lightning jump to occur based on previously reported evidence linking upward trends in kinematic and microphysical properties to increases in total flash rate (e.g., Carey and Rutledge 1996 ; Lang and Rutledge 2002 ; Tessendorf et al. 2005 ; Kuhlman et al. 2006 ; Deierling and Petersen 2008 ). Certainly, numerous studies illustrate good correlation between updraft volume, precipitation mass ice production, and flash rate (e.g., Workman and Reynolds 1949 ; Dye et

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Hunter Coleman and John Marwitz

of the cold layer is sufficiently deep, that is, >400 m, the supercooled drops may refreeze to become ice pellets ( Zerr 1997 ; Cortinas 2000 ). It is uncertain whether the effects of diabatic cooling from melting are sufficient to significantly modify the thermodynamics and kinematics of a winter storm when it occurs over homogeneous terrain. A case (12 Feb 1992) will be diagnosed and examined in terms of its thermodynamics and kinematic structure. This case was chosen because it occurred over

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David M. Schultz and Thomas Spengler

1. Introduction This comment critiques a recent paper by Qian et al. (2015) , entitled “Incorporating the effects of moisture into a dynamical parameter: Moist vorticity and moist divergence.” Qian et al. (2015) define the moist vorticity and moist divergence as the well-known kinematic quantities of vorticity and divergence multiplied by the 10th power of relative humidity. The use of these parameters is not justified scientifically or meteorologically. Hence, readers should avoid these

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Gregory S. Poulos, Douglas A. Wesley, John S. Snook, and Michael P. Meyers

improvement in skill would be found by decreasing horizontal grid spacing from 5.0 to 1.67 km. 2. Storm kinematics Overall, this event was strongly forced on the synoptic scale, with significant terrain-forced factors superimposed, such that the heaviest snowfall occurred in the foothills of the Front Range and the western portion of the Palmer Divide ( Fig. 1b ). Strong winds caused blizzard conditions over Colorado's eastern plains and snowdrifts up to 5 m (P. Wolyn 1997, personal communication). Heavy

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Shih-Yu Wang and Adam J. Clark

Figs. 1 and 2 . On the other hand, differences between forecast and observed | ∇ θ | ( Figs. 4g and 4b , respectively) are small relative to the differences in DEF, which is also a characteristic of the case in Fig. 2 . Thus, it appears that if a thermodynamic field like | ∇ θ | is used to gauge frontal intensity, only small differences are discernable between composite observed and forecast fronts; however, if a kinematic field like DEF is used to gauge the frontal intensity, the composite

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Matthew E. Gropp and Casey E. Davenport

1. Introduction The cooling and associated stabilization of the atmospheric boundary layer shortly before and immediately after local sunset, otherwise known as the nocturnal transition, leads to a series of thermodynamic and kinematic changes in the atmosphere. Limited forecasting-based research exists regarding precisely how supercells evolve during the nocturnal transition; there are numerous temporal and spatial changes that occur in the supercell’s local environment, and complex

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H. Huntrieser, H. H. Schiesser, W. Schmid, and A. Waldvogel

; Lilly 1990 ). Therefore, a variety of different thermodynamic and kinematic parameters have been derived from sounding data during the past 40 yr (see the appendix). Each of them indicated the thunderstorm potential of an air mass ( Peppler and Lamb 1989 ). Studies on the efficiency of different stability indices for the thunderstorm prediction have been presented by several authors, for example, Neumann (1971) , Anthes (1976) , Reap and Foster (1979) , Stone (1985) , Andersson et al. (1989

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Brian D. Hirth, John L. Schroeder, Christopher C. Weiss, Douglas A. Smith, and Michael I. Biggerstaff

instruments have allowed for the development of relationships between wind speeds at flight level and the ocean surface ( Hock and Franklin 1999 ; Franklin et al. 2003 ; Uhlhorn et al. 2007 ), and have helped identify prominent kinematic features within the hurricane boundary layer (HBL) including low-level wind maxima ( Powell et al. 2003 ; Kepert 2006 ; Giammanco et al. 2011 ). Though the height and magnitude of the offshore low-level wind maxima vary by storm and quadrant, wind speed profiles below

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