UNIWIPP: A University of Illinois Field Experiment to Investigate the Structure of Mesoscale Precipitation in Winter Storms

Abstract

To obtain a better understanding of the role of synoptic-scale disturbances in organizing masoscale precipitation in the midwestern United States during the winter season, and to address scientific issues regarding mesoscale dynamics of winter storms, the University of Illinois Winter Precipitation Program was conducted over a period of three winters between 1988 and 1990. The observing systems included a 10-cm wavelength meteorological Doppler radar operated by the Illinois State Water Survey, the Flatland 6-m wind profiler operated by the NOAA Aeronomy Laboratory, and an NCAR Cross-chain Loran Atmospheric Sounding System. In all, 26 storms were observed during the 3-year period. The associated precipitation ranged from highly convective storms in the warm sector to stratified clouds containing organized banded structure within the occlusion. The principle dynamical mechanisms at work often varied widely from one storm to another and sometimes within a storm. This article describes the goals and objectives of the project, as well as a few selected observations and some preliminary findings from the data gathered.