A Case Study Analysis of Heavy Snowfall Events and Road Weather Implications in 2018 in Nebraska

Weather related car accidents make up approximately a quarter of all crashes throughout the year even though the time in which they can occur is minimal in comparison to fair weather day crashes. Maintenance Decision Support Systems (MDSSs) were developed to help mitigate the number of crashes that occur during winter weather through improved operations along with reducing chemical usage. An MDSS uses weather information to recommend road treatments based on current and future weather conditions. To evaluate the limitations and capabilities of MDSS, case study analyses will be performed on two 2018 winter storms, 20-21 January and 13-14 April which occurred over the state of Nebraska. These storms were chosen because they produced heavy snowfall totals along with blizzard conditions across the state and travel delays and road closures were recorded for both events. They were both classified as Colorado Lows, which are known for the large amounts of snow they can produce. A comparison of the MDSS predictions and the National Weather Service (NWS) forecasts for each storm was done to investigate important aspects including timing the initial snowfall, snow rate intensities and snowfall durations, highlighting both the differences and similarities between the two entities. A synoptic analysis of both winter storms was done to understand their atmospheric conditions to illustrate how the MDSS handled each situation. Understanding how well the MDSS handled each storm is a key component in helping maintenance crews be more efficient utilizing the maintenance recommendations. This research will provide the Nebraska Department of Transportation (NDOT) information on the MDSS that will lead to a reduction of chemicals used to treat the roads as well as the impact they have on the environment.