Mesoscale Superensemble Forecasts with a Suite of Models over the Continental United States and North America

Using a suite of high resolution models, the forecast skills of the superensemble for precipitation and 2-meter temperature over the continental United States and North America are shown. In this study, models and/or gridded fields such as the ETA, WRFARW, MM5, NDFD, several global models, and their ensemble mean are used. The final resolution for the multimodel superensemble is at 32 km at 3-hourly temporal intervals for temperature and ¼ degree daily intervals for precipitation. The forecast length is 60 hours for temperature and 5 days for precipitation. This study utilizes an optimization for the training length (number of days) to arrive at the best results. The period of the study includes March-September 2006. The metrics for the forecast evaluation include the mean absolute error, rms error, bias, and equitable threat scores. The results show a significant improvement of the multimodel superensemble compared to its member models and their ensemble mean.