Correlation Analysis of MDSS and NEWINS

US Transportation Collection2020PDFTech ReportAnderson, Mark R.Walker, Curtis L.Barnhardt, NancyRick, NathanWunderlin, CameronUniversity of Nebraska--LincolnNebraska. Department of TransportationUnited States. Department of Transportation. Federal Highway AdministrationNebraska. Department of TransportationUnited StatesNebraskaCase studiesCorrelation analysisDecision support systemsStormsWeather forecastingWinter maintenanceM081SPR-P1(19) M081Final Report July 2018-April 2020Improving winter maintenance is a goal of most transportation agencies including the Nebraska Department of Transportation (NDOT). One approach is to develop a decision support system to aid in the winter maintenance recommendations. Iteris has developed a maintenance decision support system (MDSS) and has teamed up with NDOT to provide winter weather guidance for operations. This report investigates how well the MDSS functions for several routes across Nebraska for different storm systems. The analysis was performed from saved events within MDSS and compared to meteorological observations during different storm events, mainly Colorado or Alberta Clipper type storms that moved through and affected different regions of Nebraska. Winter severity index for the State of Nebraska (NEWINS) values were calculated for the years of study and NDOT maintenance districts around the state where the individual route segments are found. The NEWINS values were then analyzed and compared to the MDSS conditions. The NEWINS values compared favorably with the MDSS conditions, highlighting the impacts of the storms. The weather conditions produced and reported within MDSS equated well to the observational data with minor variations due mainly to differences in the distance between the route segment studied and the observation point location. There were some forecasting variations between what was observed and what was being forecasted within MDSS. Some of the variation was probably meteorological in nature; however, some were within MDSS resulting in inaccuracies in the forecasts. In most cases when there were variations in the forecast, the MDSS forecast was predicting snowfall over a longer period of time which also resulted in some cases with more forecasted snowfall than what was observed within MDSS. During the analyses, there were a few non-meteorological finds of importance. The major finding was the route segment length had a large influence on the parameters obtained for that segment within MDSS compared to segments of smaller lengths making comparison between routes a little sensitive.110