Accession Number:

ADA196875

Title:

Low-Level Outflow Potential of Non-Tornadic Thunderstorms Inferred from Single-Doppler Radar

Descriptive Note:

Doctoral thesis

Corporate Author:

AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH

Personal Author(s):

Report Date:

1988-01-01

Pagination or Media Count:

158.0

Abstract:

This research examines non-tornadic storms to improve the predictability of low-level storm outflow and to determine whether or not early signatures exist in the structures of the single-Doppler reflectivity and velocity fields that signal the development of a severe downdraft in a non- tornadic storm. By examining the magnitude and changes of radial divergence, flux, shear, and other storm parameters, inferences are made to conclude storm severity and the potential for strong low-level outflow. Storm parameters are calculated through a series of steps. After initial screening, single-Doppler data are dealiased prior to performing a running average of the velocity field. Then, a search is made along each radial for intervals over which radial divergence is indicated this is followed by predetermined shear and flux threshold tests. These intervals are used to calculate the storm parameters. Corresponding storm reflectivity fields are observed to identify fluctuations in growth and decay. Qualitative and quantitative inferences are drawn concerning the structure of the velocity and reflectivity fields and their relationship with low-level storm outflow.

Subject Categories:

  • Active and Passive Radar Detection and Equipment

Distribution Statement:

APPROVED FOR PUBLIC RELEASE