This study proposes to examine the spatial coherence of rainfall variations for different time scales, the differences in the spatial coherence between warm-season and cold-season rainfall events, and the typical movement of various rainfall events in Oklahoma for both warm-season and cold-season rainfall events. The Oklahoma Mesonet has provided valuable meteorological measurements since the early 1990's. With over 110 stations located across the state of Oklahoma, the Mesonet is a state-of-the-art network. Spatial analyses of rainfall patterns will be conducted using the rainfall data from the Oklahoma Mesonet from 1994 to 2003. This study is important because it is one of the first main rainfall studies using the Oklahoma Mesonet rainfall data. Previous studies have been conducted on this data, but using a temporal analysis instead of a specific spatial analysis.

Spatial coherence will be calculated using a basic rotated principal component analysis. Differences between the spatial coherence of rainfall between warm-season and cold-season rainfall events will be calculated. By the varying the time-scales, this study will also quantify changes in the spatial scale of rainfall variations as a function of time. This may lead to future work in characterizing typical rainfall movements during warm-season and cold-season rainfall events. The results should quantify the spatial scale separation that would be ideal for a national Mesonet system. By using a principal component method, and by separating the Oklahoma Mesonet sites into climate divisions, this study will characterize the nature of rainfall variations within each climate division, and how they differ from division to division across the state.