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David J. Bodine and Kristen L. Rasmussen

rainwater mixing ratios are also observed ahead of the leading line beneath the developing convective cores. As noted previously, θ and both decreased at low levels during surge A. The light blue contours in Fig. 12 show perturbations of −2 and −4 K, and are used as an approximation of the cold pool. At 0430 UTC, perturbations show an expanded cold pool depth and intensity with the outermost −2-K contour reaching 3 km AGL and the −4-K contour enclosing a larger volume compared to 0410 UTC. The

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Matthew D. Parker, Brett S. Borchardt, Rachel L. Miller, and Conrad L. Ziegler

convection (e.g., Colman 1990 ; Parker 2008 ); this would imply that such systems are only ingesting air parcels that originate from above the SBL. Along these lines, there are examples of nocturnal MCSs passing by surface stations with negligible fluctuations in surface temperature (e.g., Maddox 1980 ; Trier and Parsons 1993 ), which may mean that such systems lack surface cold pools and are almost totally decoupled from the SBL. This would represent a departure from the classical density current

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Rachel L. Miller, Conrad L. Ziegler, and Michael I. Biggerstaff

syntheses combining up to seven radars and continuously spanning roughly the first 3.5 h of the MCS’s lifetime. The main objectives of the present study are as follows: 1) to document the evolution of the nocturnal MCS from its elevated CI stage to a mature LL/TS system with embedded bowing segments; 2) to determine whether the CL and the storm-scale and mesoscale cold pools are elevated, surface based, or some combination of these two modes using inflow air trajectory analysis; 3) to document the MCS

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Shushi Zhang, David B. Parsons, and Yuan Wang

profile of vertical velocity from the simulation averaged over a 10 km × 10 km area centered at the leading edge of the first surge of cold air at 2100 LST. (b) As in (a), but centered on the wave propagating away from the cold pool at 2130 LST. (c) As in (b), but at 2200 LST. (d) As in (b), but for a 40 km × 40 km area ahead of the system. b. Linear wave theory and trapping of wave energy From the analysis thus far, we can state that the disturbance within the inversions lasted for ~2 h and

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Manda B. Chasteen, Steven E. Koch, and David B. Parsons

associated with a northwesterly wind surge accompanying a surface cold front that had been reinforced by convective outflow. As shown in the RAP analysis, this cold front propagated southeastward with time in tandem with an upper-level short-wave trough embedded within northwesterly flow ( Figs. 3a,b ). Fig . 2. Surface observations from (a) ASOS locations overlaid with Geostationary Operational Environmental Satellite-13 ( GOES-13 ) 10.7- μ m IR satellite imagery and (b) Oklahoma Mesonet locations

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Matthew D. Flournoy and Michael C. Coniglio

velocity observations (m s −1 ; scale at the bottom of each panel) from KFSD (relative direction shown in the upper-left panel) approximately every 5 min from 0506 to 0530 UTC at approximately 500 m AGL. The rear-inflow surge discussed in the text is highlighted in the upper-left panel. The two mesovortices that merge to form the single, observed, tornadic mesovortices are circled in pink and yellow. b. Analysis of the simulated mesovortex To analyze the evolution of MV1 ( Fig. 11i ), air parcel

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Coltin Grasmick, Bart Geerts, David D. Turner, Zhien Wang, and T. M. Weckwerth

mechanisms accelerating the leading convective line. Their study predominantly focused on internal factors such as microphysics and kinematics within the storm and their effects on downdraft velocities, hydrometeor loading, and evaporation efficiency; all of these factors strengthen cold pools and promote forward surging. The present case study similarly investigates storm propagation but focuses on the characteristics of the MCS outflow boundary and the depth and location of vertical air displacements

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Kevin R. Haghi, Bart Geerts, Hristo G. Chipilski, Aaron Johnson, Samuel Degelia, David Imy, David B. Parsons, Rebecca D. Adams-Selin, David D. Turner, and Xuguang Wang

. 1997 ), designed to measure water vapor and aerosols along their flight transects, and the Wyoming King Air with a compact Raman lidar. Time–height sections from the ground-based upward pointing profilers captured horizontal/vertical motion, moisture, and temperature. Pre- and postbore environments were sampled with atmospheric soundings and the Kansas Mesonet recorded changes in temperature, pressure, and winds. It required a lot of planning and a little luck, but the 10–11 July 2015 IOP and other

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