Snowfall Event Characteristics from a High-Elevation Site in the Southern Appalachian Mountains

Accurate assessment of snowfall patterns in high elevation remote areas is essential to providing the necessary boundary conditions for climatological analyses. The Southern Appalachian Mountain (SAM) region of the eastern U.S. provides a unique study area due to its low latitude and proximity to the Gulf of Mexico and Atlantic Ocean. Major snowstorms, such as Hurricane Sandy in October 2012, can result in heavy snowfall of 100 cm or greater in favored upslope regions. To contribute to this understanding, the MObile Precipitation Research And Monitoring (MOPRAM) station was deployed at Roan Mountain (1875 m asl.) on the Tennessee/North Carolina border in October 2012. MOPRAM has allowed for the analysis of hourly variables such as temperature, liquid precipitation, and snow depth during the 2012-13 snow season. In this paper, observed snowfall event characteristics are analysed and compared with those of other sites in the SAM. The 25 snow events were characterized by conditionally unstable upstream lapse rates, northwest winds, high-to-low elevation precipitation enhancement near a factor of three, and 364 mm of seasonal snow liquid equivalent on Roan Mountain. An estimated 391 cm of snow fell at Roan during the 2012-2013 season when using nearby snow liquid ratios to estimate snowfall.