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Introduction Forecasting and Operations Hail Storm Summary and Future Work Tornadic Supercell Mesoscale Convective System Radar

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Introduction Forecasting and Operations Hail Storm Summary and Future Work Tornadic Supercell Mesoscale Convective System Radar Radar Observations of Storms for Education Megan Amanatides, Sara Berry, Nicole Corbin, Jason Endries, Matthew Miller, and Sandra Yuter Department of Marine, Earth, and Atmospheric Sciences – North Carolina State University, Raleigh, NC To illustrate the complex, evolving nature Scanning sequences Introduction Radar Data Collection of storms, we tailored a scan strategy that NCAR S-Pol CSU-CHILL included vertical cross-sections and volume Horizontal scan A Horizontal scan B Schematics and conceptual model diagrams are a Vertical cross-section Reset and pause cornerstone of mesoscale precipitation systems scans updating every 3 minutes. Research education in the university meteorology curriculum. radars were required since National S-Pol These drawings allow students to visually simplify the Weather Service operational radars do not complicated dynamics of the systems they are studying. take vertical cross sections and update CHILL The use of conceptual models has been shown to volume scans every 6+ minutes. 0:00 3:00 6:40 measurably increase student understanding, particularly when they are made available to compare Hail storm Tornadic Supercell and contrast with real Plan View Vertical Cross-section Plan View Vertical Cross-section Classic supercell data (Gilbert and Ireton, 18 Reflectivity Reflectivity radar signatures o 1.5 tilt 2003: Understanding 1.5o tilt 18 Reflectivity such as a Models in Earth and Adapted from K.A. Browning et al., 1976: Structure of an Evolving Hailstorm Part V: Synthesis and implications for Hail Growth and Hail Suppression. Mon. Wea. Rev., 104, 603–610. 0 bounded weak Space Science). 18 Particle ID echo region, 0 90 km High turbulence Height (km AGL) Height (km hook echo, and Pol (km) Pol - 0 v-notch are 18 0 0 20 40 60 Radial Velocity shown in the More Laminar Flow 50 km Distance from S-Pol (km) AGL) (km Height particle ID and Distance from S Distance 18 reflectivity fields. 0 Spectrum Width 50 18 Spectrum Width Mid-level rotation associated with a 90 km mesocyclone is 0 AGL) Height (km 0 50 0 20 40 60 80 observed in the Distance from S-Pol (km) Distance from S-Pol (km) 4o tilt 0 0 20 40 60 radial velocity Arrow on the left panel indicates the location of the vertical cross- 50 km Distance from S-Pol (km) Ice Graupel plan view panel. Rain section. 1.5” hail was reported in this area east of Denver, CO at Hail this time. In contrast to the schematic to the left, the hail region High turbulence is observed both at the interface between opposing extends much further into the storm. flows and within the main updraft. We are developing a series of guided case studies of commonly observed storm structures for use in upper Mesoscale Convective System Reflectivity (dBZ) level undergraduate and graduate mesoscale 0 20 40 60 Plan View Vertical Cross-section Color Particle ID meteorology courses. Data were collected from two Cloud drops Rain Hail Graupel Ice Snow Non-meteorological 100 14 Reflectivity Reflectivity Melting ice Radial Velocity (m/s) NSF research radars in Colorado, CSU-CHILL and o Scales 4 tilt -30 -18 -6 6 18 30 NCAR S-Pol, from 20 May to 20 June 2014 0 Spectrum Width (m/s) 0 2.4 4 6.4 8 50 14 Particle ID Mountains Forecasting and Operations CHILL (km) CHILL - Summary and Future Work Undergraduate students at NCSU operated the two 0 Undergraduate students simultaneously learned more about storms and radars and forecasted the potential for convective 0 14 Radial Velocity radar operations during a month-long data collection campaign. A diverse activity. Forecasts included times of convective initiation AGL) (km Height and dissipation as well as convective mode. The 0 radar dataset including hailstorms, stratiform precipitation, ordinary Distance from CSU from Distance students made real time decisions on the locations for 50 14 Spectrum Width thunderstorms, and a tornadic supercell was acquired during this project. vertical cross-sections during operations. The vertical cross-sections in particular provide great detail on the airflows 0 and hydrometeor types within these storms. These data will be used in 100 50 0 80 60 40 20 0 Distance from CSU-CHILL (km) Distance from CSU-CHILL (km) guided modules that will supplement schematic diagrams commonly used Line of strong convection with stratiform precipitation to the north. in mesoscale meteorology courses. While the stratiform region exhibits a simple, layered flow, the Acknowledgements (1) convective region has more complicated flow with small flow We would like to thank the National Center for Atmospheric Research Earth Observing Laboratory S-Pol radar facility, and the Above: S. Berry and M. Amanatides Colorado State University CHILL radar facility for their contributions. Special thanks to Scott Ellis and Pat Kennedy for their support Right: S. Berry, N. Corbin, M. Amanatides, J. Endries branches. during the field phase of the project. This material is based upon work supported by the National Science Foundation (AGS-1303025). (1) .
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