Spatial Forecasts of Maximum Hail Size Using Prognostic Model Soundings and HAILCAST

Abstract Forecasting the occurrence of hail and the maximum hail size is a challenging problem. This paper investigates the feasibility of producing maps of the forecast maximum hail size over the Canadian prairies using 12-h prognostic soundings from an operational NWP model as input for a numerical hail growth model. Specifically, the Global Environmental Multiscale model run by the Canadian Meteorological Center is used to provide the initial data for the HAILCAST model on a 0.5° × 0.5° grid. Maps depicting maximum hail size for the Canadian prairies are generated for 0000 UTC for each day from 1 June to 31 August 2000. The forecast hail-size maps are compared with radar-derived vertically integrated liquid data over southern Alberta and surface hail reports. Verification statistics suggest that the forecast technique is skillful at identifying the occurrence of a hail day versus no-hail day up to 12 h in advance. The technique is also skillful at predicting the main threat areas. The maximum diameter ...

[1]  Z. Janjic.  The Step-Mountain Eta Coordinate Model: Further Developments of the Convection, Viscous Sublayer, and Turbulence Closure Schemes , 1994 .

[2]  Richard L. Thompson,et al.  Nationwide comparisons of hail size with WSR-88D vertically integrated liquid water and derived thermodynamic sounding data , 1998 .

[3]  Michael E. Baldwin,et al.  Properties of the Convection Scheme in NCEP's Eta Model that Affect Forecast Sounding Interpretation , 2002 .

[4]  Cynthia K. Mueller,et al.  The Utility of Sounding and Mesonet Data to Nowcast Thunderstorm Initiation , 1993 .

[5]  J. Fritsch,et al.  Numerical Prediction of Convectively Driven Mesoscale Pressure Systems. Part I: Convective Parameterization , 1980 .

[6]  G. Reuter,et al.  A radar‐based methodology for preparing a severe thunderstorm climatology in central Alberta , 2004 .

[7]  Ruixin Yang,et al.  Evaluations of Mesoscale Models' Simulations of Near-Surface Winds, Temperature Gradients, and Mixing Depths , 2001 .

[8]  A. Staniforth,et al.  The Operational CMC–MRB Global Environmental Multiscale (GEM) Model. Part I: Design Considerations and Formulation , 1998 .

[9]  G. Reuter,et al.  Modeling Maximum Hail Size in Alberta Thunderstorms , 2002 .

[10]  Charles A. Doswell,et al.  On the Environments of Tornadic and Nontornadic Mesocyclones , 1994 .

[11]  M. Yau,et al.  The Causes of Severe Convective Outbreaks in Alberta. Part II: Conceptual Model and Statistical Analysis , 1993 .

[12]  Donald S. Foster,et al.  A Hail Size Forecasting Technique , 1956 .

[13]  Caren Marzban,et al.  A Bayesian Neural Network for Severe-Hail Size Prediction , 2001 .

[14]  John P. Pino,et al.  An Interactive Method for Estimating Maximum Hailstone Size from Forecast Soundings , 1990 .

[15]  J. Brimelow.  Numerical modelling of hailstone growth in Alberta storms , 1999 .

[16]  M. Dixon,et al.  TITAN: Thunderstorm Identification, Tracking, Analysis, and Nowcasting—A Radar-based Methodology , 1993 .

[17]  Richard L. Thompson,et al.  Eta Model storm-relative winds associated with tornadic and nontornadic supercells , 1998 .

[18]  Greg Stumpf,et al.  The S2K Severe weather detection algorithms and their performance , 2004 .

[19]  J. B. Maxwell,et al.  Forecasting Hailfall in Alberta , 1977 .

[20]  A. Betts.  A new convective adjustment scheme. Part I: Observational and theoretical basis , 1986 .

[21]  A. Witt,et al.  An Enhanced Hail Detection Algorithm for the WSR-88D , 1998 .

[22]  David J. Stensrud,et al.  Using Initial Condition and Model Physics Perturbations in Short-Range Ensemble Simulations of Mesoscale Convective Systems , 2000 .

[23]  S. Brun,et al.  A note on Canada's hail climatology: 1977–1993 , 1999 .

[24]  A. Betts,et al.  A new convective adjustment scheme. Part II: Single column tests using GATE wave, BOMEX, ATEX and arctic air‐mass data sets , 1986 .

[25]  G. Reuter,et al.  Operational Forecasts of Maximum Hailstone Diameter in Mendoza, Argentina , 2018, The Journal of Weather Modification.

[26]  S. Changnon.  Temporal and Spatial Relations between Hail and Lightning , 1992 .

[27]  Tammy M. Weckwerth,et al.  The Effect of Small-Scale Moisture Variability on Thunderstorm Initiation , 2000 .

[28]  The Use of Hourly Model-Generated Soundings to Forecast Mesoscale Phenomena. Part I: Initial Assessment in Forecasting Warm-Season Phenomena , 1998 .

[29]  Wayne E. McGovern,et al.  The WSR-88D Severe Weather Potential Algorithm , 1995 .

[30]  R. B. Charlton,et al.  Urban hailstorms: a view from Alberta , 1995 .

[31]  G. Grell.  Prognostic evaluation of assumptions used by cumulus parameterizations , 1993 .

[32]  Richard L. Thompson,et al.  Close Proximity Soundings within Supercell Environments Obtained from the Rapid Update Cycle , 2003 .

[33]  Ryan E. Jewell,et al.  Evaluation of Alberta Hail Growth Model Using Severe Hail Proximity Soundings from the United States , 2004 .

[34]  Ying-Hwa Kuo,et al.  Semiprognostic Tests of Cumulus Parameterization Schemes in the Middle Latitudes , 1988 .

[35]  Caren Marzban,et al.  A Neural Network for Damaging Wind Prediction , 1998 .

[36]  Thomas M. Hamill,et al.  Conditional Probabilities of Significant Tornadoes from RUC-2 Forecasts , 2000 .

[37]  H. Fuelberg,et al.  An Evaluation of WSR-88D Severe Hail Algorithms along the Northeastern Gulf Coast , 1998 .

[38]  Charles A. Doswell,et al.  On the Use of Mesoscale and Cloud-Scale Models in Operational Forecasting , 1992 .

[39]  A. Staniforth,et al.  The Operational CMC–MRB Global Environmental Multiscale (GEM) Model. Part II: Results , 1998 .

[40]  J. Kain,et al.  Convective Parameterization for Mesoscale Models: The Fritsch-Chappell Scheme , 1993 .

[41]  Roger A. Pielke,et al.  Human Factors Explain the Increased Losses from Weather and Climate Extremes , 2000 .

[42]  N. A. Crook.  Sensitivity of Moist Convection Forced by Boundary Layer Processes to Low-Level Thermodynamic Fields , 1996 .

[43]  Mark M. Wheeler,et al.  Verification of High-Resolution RAMS Forecasts over East-Central Florida during the 1999 and 2000 Summer Months , 2002 .