Tornado Outbreak Modeling Student Experience

Andrew Mercer, Mississippi State University

Usage Details

This project is part of the Blue Waters Student Internship Program. The goal of this project is the development of an error growth function for forecasts of tornadic severe weather outbreaks using a high-resolution mesoscale model. The student will be working with the WRF-ARW forecast model at a high spatial (12 km) and temporal (time steps of 30 seconds) resolution for 5 major tornado outbreaks. Each outbreak will be simulated in initial condition ensemble mode, yielding 10 forecasts for each case at 5 varying lead times to the outbreak (24-hour, 48-hour, 72-hour, 96-hour, and 120-hour), to ascertain the sensitivity of the spread in the 10-member ensemble to lead time. This spread will be used to formulate an error growth function by lead time for numerous common severe weather diagnostic variables. Further, the student will use the output to determine spatial uncertainty metrics in the results using the R software. This project will build upon results from a previous Blue Waters internship studying non-tornadic outbreaks and allow for a direct comparison of each outbreak type in the context of spatial and temporal uncertainty. Ultimately, this project has the potential to help forecasters with outbreak forecasts by providing additional evidence as to the limit of the forecast ability of severe weather outbreaks at lead times of more than a day and addresses the challenge of medium-term forecasting of outbreaks.