Skill of 1- and 4-km WRF-ARW Forecasts of Storm Mode and Motion

In this study, forecasts of supercell motion in WRF-ARW models at 1- and 4-km grid spacing are compared to observed storm motions over the 2009-10 convective seasons. The trajectories of these forecast and observed storms are determined by utilizing an objective tracking technique. An analysis of the skill of WRF-ARW models at explicitly predicting convective motion is also compared to environment-based techniques (e.g. Bunkers motion). The extent to which grid spacing (1-km versus 4-km) influences forecast skill for these storms is also explored. Preliminary results of this research will be presented at the conference.