VORTEX-SE: Improving Radar Wind Retrievals in Potentially Tornadic Storms in the Southeast United States

Although three-dimensional wind retrievals from multiple-Doppler radar observations are a common tool for severe storm analyses, few examples have been presented from cases examined in the Southeastern U.S. Accurate multiple-Doppler radar wind retrievals require quantification of wind shear below the lowest matched radar scan elevation (often ~100- 300 m AGL even in high-density research deployments). Multiple-Doppler wind retrievals in severe storms, which can contain intense horizontal convergence and updrafts near the ground, often are performed for storms targeted in relatively flat and vegetation-free regions of the Plains. Extrapolation assumptions that are error prone even in these relatively flat conditions are more problematic in areas with more complex terrain and varied vegetation.

Using multi-Doppler and in situ data gathered from the 2017 field phase of the VORTEX-SE project, we are working to refine and improve the accuracy of three-dimensional wind retrieval solutions through incorporation of surface mesonet data and lower boundary conditions representative of terrain features in the southeast. We will present preliminary wind retrieval results using these refined techniques.