Statistical Objective Analysis of Dual-Doppler Radar Data from a Tornadic Storm

Abstract

The horizontal wind and reflectivity fields in a tornadic storm are investigated with dual-Doppler radar. Emphasis is placed on a statistical objective analysis technique of the Eddy-Gandin type for determining these fields at grid-points. A space-time correction is first made to the observations. Weighting of data to grid-points with a linear regression model required computation of a spatial autocorrelation function for different storm regions. This function was found to fall off faster vertically than horizontally, and is quite dependent on storm structure. The analyzed fields were reasonably smooth. The low-level storm structure revealed an intense tornado cyclone with a corresponding weak echo region, barrier flow of environmental winds, and several other interesting features.