Date of Award


Document Type


Degree Name

Master of Science (MS)


Atmospheric Science

Committee Chair

Kevin Knupp

Committee Member

Lawrence Carey

Committee Member

Timothy Lang

Committee Member

Brian Carcione


Freezing precipitation--Forecasting., Hydrometeorology.


A Northern Alabama winter storm from February 20-21, 2015 is examined to determine the characteristics of precipitation transition. The primary data sources include profiler data from the University of Alabama in Huntsville (UAH) Mobile Integrated Profiling System (MIPS) and two dual polarization radars, the Advanced Radar for Meteorological and Operational Research (ARMOR) C-Band and the NOAA KHTX WSR-88D S-Band radar. Using typical precipitation fall speeds, integrated liquid water from the MIPS MPR, 915 MHz profiler Doppler spectra, and temperature, a hydrometeor identification process was developed. A hydrometeor classification algorithm developed by Colorado State University was performed on the radar data. When compared with verification data, the final transition was determined as (dry) snow/aggregates to rimed snow to mixed ice precipitation (ice pellets, wet snow/aggregates) to freezing rain to rain. The importance of including the profiler HID is seen through four additional precipitation types that the radar HCA did not include.



To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.