A study of nocturnal inversions in the Central Plains of the United States was conducted using 17 sites. Radiosonde data from 1960 to 2007 were analyzed. Changes in frequency, intensity, and depth of nocturnal inversions over the span of those 48 years are documented. Land-use classifications of each site and the surrounding area are compared to each site's respective change in inversion characteristics. The trends found in these changes may also lead to trends in air-quality, especially over urban areas. Agricultural applications of these results have also been noted. Significant changes in inversion characteristics may be used as a proxy for measuring local and regional climate change.