He is a professor emeritus in the Department of Atmospheric Science at the Colorado State University (CSU).

His current interests are largely in the area of observation and modeling of larger clusters of thunderstorms that occur preferentially at night over the central United States, the simulation of severe thunderstorms including tornadoes and the application of the RAMS cloud-resolving atmospheric model to forecasting agriculture and aviation impact variables.

He has held positions at the Experimental Meteorological Laboratory (ERL), the National Oceanic and Atmospheric Administration (NOAA), and the United States Department of Commerce, and served as the head of the Numerical Simulation Group from 1970 to 1974.

[2] Working with students who provided coding expertise as well as original scientific insights (including Chaing Chen, Piotr J. Flatau, Michael D. Moran, Jerome Schmidt, Craig J. Tremback, Gregory Tripoli) he developed one of the first comprehensive mesoscale weather forecast models in the U.S. – the Regional Atmospheric Modeling System (RAMS).

[3] This modelling system was subsequently merged with a smaller subset of the code based on the mesoscale model developed independently by Roger A. Pielke for his Ph.D. research related to sea breeze studies and subsequently with his students at the Colorado State University.