Tornado Identification from Analyses of Digital Radar Data.
Abstract
An investigation was conducted to determine whether tornadoes presented a unique signature in analyses of digital radar data from central Oklahoma during the Spring. The data were collected by the 10-cm-WSR-57 radar at the National Severe Storms Laboratory at Norman, Oklahoma. Three types of numerical analyses were used in this study: constant-altitude reflectivity maps (CAZM), total vertically-summed reflectivity maps (TVSZ), and partial vertically-summed reflectivity maps (PVSZ), with greatest emphasis placed on the PVSZ maps. Presentations covering a 100-km square were constructed at either 5 to 10 min intervals. From the analysis of three case studies during during 1974 and 1975, that contained five tornadoes, it was concluded that tornadoes did not produce a singular identifying signature in analyses of digital radar data, but rather produced a combination of features which indicated, with a high probability, the presnce of a tornado. Such features were the appearance of a small area of reduced reflectivity known as a Bounded Weak-Echo Region (BWER), a tilt of the core of the storm toward the BWER, and a rapid decrease in the upper-level mass of the storm as indicated by a rapid decrease in the reflectivity of the upper PVSZ.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1976
- Accession Number
- ADA047816
Entities
People
- Donald Wayne Pittman
Organizations
- Air Force Institute of Technology