Weather and Forecasting: Recent submissions

Now showing items 2461-2480 of 3043

    • Evaluating the Performance of WSR-88D Severe Storm Detection Algorithms 

      Witt, Arthur; Eilts, Michael D.; Stumpf, Gregory J.; Mitchell, E. De Wayne; Johnson, J. T.; Thomas, Kevin W. (American Meteorological Society, 1998)
      This paper discusses some important issues and problems associated with evaluating the performance of radar-based severe storm detection algorithms. The deficiencies of using Storm Data as a source of verification are ...

    • Nomogram for Aiding the Interpretation of Tornadic Vortex Signatures Measured by Doppler Radar 

      Brown, Rodger A. (American Meteorological Society, 1998)
      A technique is described whereby an investigator can obtain a more representative peak velocity for a tornadic vortex signature (TVS) than can be obtained by using the extreme measured Doppler velocities associated with ...

    • WSR-88D Radar Depiction of Supercell–Bow Echo Interaction: Unexpected Evolution of a Large, Tornadic, “Comma-Shaped” Supercell over Eastern Oklahoma 

      Wolf, Peter L. (American Meteorological Society, 1998)
      During a severe thunderstorm outbreak on 17 April 1995, a bowing line segment of severe thunderstorms intercepted an isolated supercell over eastern Oklahoma. The result of the supercell?bow echo interaction was unexpected. ...

    • Doppler Radar Analysis of a Snake River Plain Convergence Event 

      Andretta, Thomas A.; Hazen, Dean S. (American Meteorological Society, 1998)
      A convergence zone periodically forms in the Snake River plain (SRP) of eastern Idaho as a result of terrain-induced boundary layer flow under synoptic northwesterly flow at low and midlevels. Complex terrain in central ...

    • Bird Migration and Bias of WSR-88D Wind Estimates 

      Gauthreaux, Sidney A.; Mizrahi, David S.; Belser, Carroll G. (American Meteorological Society, 1998)
      Migrating birds can greatly influence base velocity, velocity azimuth display (VAD), and VAD wind profile products of the WSR-88D. This is documented by comparing estimates of wind velocity and direction from these products ...

    • Displays of Bird Movements on the WSR-88D: Patterns and Quantification 

      Gauthreaux, Sidney A.; Belser, Carroll G. (American Meteorological Society, 1998)
      The WSR-88D can readily detect birds in the atmosphere in both clear air and precipitation mode, and echo reflectivities of 30?35 dBZ may be realized during heavy migration events or when birds are departing a roosting ...

    • A Study of the Evolution of Mesoscale Convective Systems Using WSR-88D Data 

      Hilgendorf, Eric R.; Johnson, Richard H. (American Meteorological Society, 1998)
      While mesoscale convective systems (MCSs) are major contributors to severe weather and precipitation in the central United States, details of their evolution are still not fully understood. In particular, recent observational ...

    • Rainfall Estimation by the WSR-88D for Heavy Rainfall Events 

      Baeck, Mary Lynn; Smith, James A. (American Meteorological Society, 1998)
      Storms that produce extreme flooding present a special challenge for the WSR-88D rainfall algorithms. The authors assess the utility of weather radar in the investigation of extreme rain-producing storms through both ...

    • Estimation of Rainfall for Flood Prediction from WSR-88D Reflectivity: A Case Study, 17–18 October 1994 

      Vieux, Baxter E.; Bedient, Philip B. (American Meteorological Society, 1998)
      Flood forecasting requires accurate estimates of the spatial and temporal rainfall rates over a catchment. Depending on the Z?R relationship and threshold values, processing of WSR-88D reflectivity data affects the rainfall ...

    • Calibration of the WSR-88D Precipitation Processing Subsystem 

      Anagnostou, Emmanouil N.; Krajewski, Witold F. (American Meteorological Society, 1998)
      The WSR-88D Precipitation Processing Subsystem (PPS) is a multicomponent rainfall-estimation algorithm with a large number of parameters controlling its performance. Currently, the parameter values of the PPS are set based ...

    • The WSR-88D Rainfall Algorithm 

      Fulton, Richard A.; Breidenbach, Jay P.; Seo, Dong-Jun; Miller, Dennis A.; O’Bannon, Timothy (American Meteorological Society, 1998)
      A detailed description of the operational WSR-88D rainfall estimation algorithm is presented. This algorithm, called the Precipitation Processing System, produces radar-derived rainfall products in real time for forecasters ...

    • Optimizing the WSR-88D Mesocyclone/Tornadic Vortex Signature Algorithm Using WATADS—A Case Study 

      Tipton, Gregory A.; Howieson, Eric D.; Margraf, John A.; Lee, Robert R. (American Meteorological Society, 1998)
      A tornado outbreak occurred in east-central Minnesota around 0000 UTC 22 July 1995, within 80 km of the KMPX WSR-88D, at the Minneapolis?Chanhassen Weather Service Forecast Office (WSFO). The WSR-88D Mesocyclone/Tornadic ...

    • The National Severe Storms Laboratory Tornado Detection Algorithm 

      Mitchell, E. De Wayne; Vasiloff, Steven V.; Stumpf, Gregory J.; Witt, Arthur; Eilts, Michael D.; Johnson, J. T.; Thomas, Kevin W. (American Meteorological Society, 1998)
      The National Severe Storms Laboratory (NSSL) has developed and tested a tornado detection algorithm (NSSL TDA) that has been designed to identify the locally intense vortices associated with tornadoes using the WSR-88D ...

    • Improvement of the WSR-88D Mesocyclone Algorithm 

      Lee, Robert R.; White, Anderson (American Meteorological Society, 1998)
      The build 9 Weather Surveillance Radar-1988/Doppler mesocyclone algorithm (B9MA) is designed to locate mesocyclones [rotating thunderstorm updrafts with diameters between 1.8 and 9.2 km (1?5 n mi)]. Because there is less ...

    • The Radar “Three-Body Scatter Spike”: An Operational Large-Hail Signature 

      Lemon, Leslie R. (American Meteorological Society, 1998)
      Recently, a rare radar artifact called the ?flare echo? or ?three-body scatter signature? has been examined by several researchers. Here, this midlevel storm signature is called the ?three-body scatter spike? (TBSS) and ...

    • The National Severe Storms Laboratory Mesocyclone Detection Algorithm for the WSR-88D 

      Stumpf, Gregory J.; Witt, Arthur; Mitchell, E. DeWayne; Spencer, Phillip L.; Johnson, J. T.; Eilts, Michael D.; Thomas, Kevin W.; Burgess, Donald W. (American Meteorological Society, 1998)
      The National Severe Storms Laboratory (NSSL) has developed a mesocyclone detection algorithm (NSSL MDA) for the Weather Surveillance Radar-1988 Doppler (WSR-88D) system designed to automatically detect and diagnose the ...

    • An Enhanced Hail Detection Algorithm for the WSR-88D 

      Witt, Arthur; Eilts, Michael D.; Stumpf, Gregory J.; Johnson, J. T.; Mitchell, E. De Wayne; Thomas, Kevin W. (American Meteorological Society, 1998)
      An enhanced hail detection algorithm (HDA) has been developed for the WSR-88D to replace the original hail algorithm. While the original hail algorithm simply indicated whether or not a detected storm cell was producing ...

    • Nationwide Comparisons of Hail Size with WSR-88D Vertically Integrated Liquid Water and Derived Thermodynamic Sounding Data 

      Edwards, Roger; Thompson, Richard L. (American Meteorological Society, 1998)
      This study tests hypothetical correspondences between size of severe hail, WSR-88D derived vertically integrated liquid water (VIL), and an array of thermodynamic variables derived from computationally modified sounding ...

    • The Storm Cell Identification and Tracking Algorithm: An Enhanced WSR-88D Algorithm 

      Johnson, J. T.; MacKeen, Pamela L.; Witt, Arthur; Mitchell, E. De Wayne; Stumpf, Gregory J.; Eilts, Michael D.; Thomas, Kevin W. (American Meteorological Society, 1998)
      Accurate storm identification and tracking are basic and essential parts of radar and severe weather warning operations in today?s operational meteorological community. Improvements over the original WSR-88D storm series ...

    • An Update on the NEXRAD Program and Future WSR-88D Support to Operations 

      Crum, Timothy D.; Saffle, Robert E.; Wilson, James W. (American Meteorological Society, 1998)
      The operational network of WSR-88D systems is in place. These radars provide a large increase in performance and coverage over the radars they replaced?and in some locations are the first operational weather radars. The ...