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Yun Lin, Jiwen Fan, Jong-Hoon Jeong, Yuwei Zhang, Cameron R. Homeyer, and Jingyu Wang

(SPC) ( Fig. 1f ). Hailstones up to 3 in. (1 in. = 2.54 cm) in diameter were reported by SPC and wind gusts exceeded 74 miles per hour (1 mph ≈ 0.45 m s −1 ) were observed over a large area ( Fig. 1f ). Limited hailstone reports are probably because of the local nighttime and the low population density after passing over Kansas City. Fig . 1. Radar reflectivity from the KEAX NEXRAD at the plan position indicator (PPI) scan on a 0.9° elevation at (a) 2300 UTC 1 Jul, (b) 2329 UTC 1 Jul, and (c) 0001

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Samuel K. Degelia, Xuguang Wang, and David J. Stensrud

event is improved compared to assimilating these observations using rawinsonde errors (not shown). Geer and Bauer (2011) and Minamide and Zhang (2017) use a similar approach to inflate observation error covariances for microwave imager radiances. This technique is only meant as a preliminary method for assimilating the AERI and Doppler lidar observations. In the future, we plan to further develop an optimal method for determining observation errors for these instruments. c. Design of the model

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Elizabeth N. Smith, Joshua G. Gebauer, Petra M. Klein, Evgeni Fedorovich, and Jeremy A. Gibbs

plan position indicator (PPI) scans and periods of staring vertically to sample the horizontal and vertical wind, respectively ( Turner 2016c , d ; Delgado et al. 2015 ; Hanesiak and Turner 2016 ). The Doppler lidar data were passed through a signal-to-noise ratio (SNR) check for validity. Following the analysis in Päschke et al. (2015) , we determined that a threshold of was acceptable for removing noisy data and providing reasonable data availability. Then, the data were only used in the

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

of 0350 UTC and 0550 UTC, respectively). Each of the WRF depictions occurs 20 min after the tracer reset procedure described in section 2a . Fig . 9. Depiction of selected fields at t = 0130 from the CM1 simulation: (a) plan view of simulated logarithmic radar reflectivity factor at the bottom model level (dB Z , shaded); (b) vertical cross section of passive tracer concentrations originating from four layers (shaded by the tracer with the greatest concentration in each grid cell, with 0

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Aaron Johnson, Xuguang Wang, and Samuel Degelia

advance of the arrival of the cold pool. Thus, as hypothesized, the higher effective resolution [~7 times grid spacing; Skamarock (2004) ] of approximately 7 km in the 1-km simulation is able to better resolve the borelike features than the 4-km grid with an effective resolution of about 28 km. Further experiments are planned to determine if 1-km grid spacing is sufficient to adequately predict the important details of bores or if even higher resolution provides further advantages. Errors in the

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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

deemed the potential for bore development medium-to-high based on a theory-based algorithm that characterized the conditions necessary to develop and sustain a bore. The theoretical parameters of the algorithm were calculated from data produced in multiple convection-allowing models, including experimental ones. Urgently, the bore lead scientist disseminated the travel plans for the mobile PECAN Integrated Sounding Arrays (mPISAs), the mobile sounding vehicles, and the mobile radar trucks through

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John M. Peters, Erik R. Nielsen, Matthew D. Parker, Stacey M. Hitchcock, and Russ S. Schumacher

prior to the initiation of the Iowa MCS (the MCS occurred between 0000 and 1200 UTC 25 June). The CSUWRF was one of many convection-allowing models that were used during PECAN as guidance for mission planning ( Geerts et al. 2016 ). The second version 3.4.1 WRF simulation was configured with the RAP analysis as ICs and LBCs in an attempt to produce a simulation that closely resembled the observed MCS evolution [this simulation is hereafter referred to as the downscaled RAP (DSRAP)]. The DSRAP

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Aaron Johnson and Xuguang Wang

distribution of microphysics schemes is skewed toward Thompson while also including at least one member with each of the other four microphysics schemes. Third, a 10-member subensemble with Thompson microphysics and two of each PBL scheme is included to facilitate planned future studies on PBL scheme sensitivities. The second multiphysics ensemble (MULTI2) provides an alternative configuration based on evenly distributing the three of the better performing PBL and MP schemes across the ensemble members

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Thomas R. Parish

Fig. 6a ). Fig . 6. (a) Map of the Great Plains states including the PECAN study area (dashed line). Thick, solid line indicates fixed track of UWKA for LLJ flights. (b) Schematic of flight plan along fixed track showing vertical sawtooth profiling east–west (dark solid line) and west–east (dark dashed line) and isobaric leg (thick gray dashed line). Details of the sawtooth profiling along the fixed track are shown in Fig. 6b . Starting on the east end of the fixed track, vertical sawtooth

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Thomas R. Parish and Richard D. Clark

38.7°N between longitudes 98.9° and 100.3°W (see dark solid line in Fig. 2a for track). Fig . 2. (a) Map of the Great Plains states including the PECAN study area (dashed rectangle). The thick solid line indicates the fixed track of UWKA for the LLJ flight on 20 Jun 2015. (b) A schematic drawing of the flight plan along the fixed track, showing vertical sawtooth profiling from east to west (dark solid line) and the isobaric leg (thick gray dashed line). Details of the sawtooth profiling along

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