Synoptic Classification of Ohio River Basin Snowfall Events

Snowfall plays a crucial role in the Ohio River Basin, impacting transportation, local economies, and ecosystems. As snow melts, it replenishes soil moisture, supports plant growth, and insulates plants and animals from harsh winter temperatures. Over the past 75 years, significant changes have been observed in the region’s snowfall patterns, including decreased frequency and magnitude, which have had widespread societal and environmental effects. This research examines these trends by analyzing daily snowfall records since 1948, investigating spatial distribution of snowfall, and assessing the synoptic-scale atmospheric drivers of snowfall events. The three main snowfall producing weather patterns identified included those with northwest flow with the potential for lake-effect snowfall in the northeast portion of the basin, mid-latitude cyclones that produced wrap-around or frontal snowfall in the southern and central portions of the basin, and high-pressure systems that lead to lighter snowfall. Over half of the snowfall days were driven by patterns suitable for lake-effect snowfall, highlighting the significant role that this synoptic feature has in bringing snow to the basin. Depending on the factors influencing regional and local scales, the frequency and magnitudes of these snowfall events varied throughout time, showing both decreasing and increasing trends, forced in part due to significant associations with the Arctic and North Atlantic Oscillations. The dynamics of these large-scale synoptic systems highlights the importance of understanding how these patterns affect snowfall variability. With important implications for future research on regional snowfall and weather impacts, this study provides insight into how snowfall trends are evolving overtime.