20th Conference on Severe Local Storms5B.1
An overview of the Severe Thunderstorm Electrification and Precipitation Study (STEPS)
Morris L. Weisman, NCAR, Boulder, CO; and L. J. Miller
The STEPS field program will be conducted in Eastern Colorado and
Western Kansas from 22 May to 16 July 2000. The broad goal of STEPS is
to achieve a better understanding of the interactions between
kinematics, precipitation production, and electrification in severe
thunderstorms on the High Plains. The specific scientific objectives
include:
- To understand the apparent major differences in storm processes
that have led supercells to be considered as either low, medium (also
referred to as classic) or heavy precipitation (LP, MP, and HP)
producers.
- To understand how observed differences in the distribution of
precipitation and cloud particles in different types of severe storms
cause systematic differences in the way these storms electrify and in
the types and rates of intracloud and cloud-to-ground lightning that are
produced.
- To verify and/or to improve inferences of precipitation type from
polarimetric radar measurements.
The primary instrumentation includes the NCAR S-Pol, CSU Chill and the
NWS Goodland WSR-88D radars for multiparameter and Doppler wind
observations, the South Dakota School of Mines and Technology T28
armored aircraft for in situ microphysical observations within storm
updrafts, a three dimensional lightning mapping system from the New
Mexico Institute of Mining and Technology, balloon-borne electrification
measurements and mobile mesonets from the National Severe Storms Lab,
and two mobile sounding units from NCAR. In this presentation, we will
review the scientific motivation for the STEPS program and summarize the
range of datasets obtained during the field phase. This talk will
especially emphasize the precipitation studies aimed at understanding
the differences between LP, Classic, and HP supercells.
Session 5B, Storm electrification, lightning, and STEPS (Parallel with Session 5A)
Wednesday, 13 September 2000, 8:00 AM-10:00 AM
Next paper
Browse or search entire meeting
AMS Home Page