Use of a Road Surface Model within the National Weather Service

As the National Weather Service (NWS) pursues the goal of a weather-ready nation, there is an increasing need for scientific tools that enhance our ability to provide high-quality forecasts and decision support services. One such tool is the Model of the Environment and Temperature of Roads (METRo), a road surface condition forecasting model developed and maintained at Environment Canada. METRo utilizes site-specific metadata, roadway observations, and gridded atmospheric forecasts to physically resolve the interactions between predicted moisture and the road surface. Previous case studies have shown that METRo can add value by providing NWS forecasters with the information they need to anticipate high-impact road weather events.

At NWS Western Region Headquarters, METRo is run hourly for all Western Region (and many Central Region) road weather information system (RWIS) sensors providing sufficient observations. METRo output is available to NWS forecasters via an internal Google Maps display that uses colored icons to indicate predicted conditions at each site. Clicking an icon presents detailed forecast information for that site, including road surface temperature and conditions. Other quantities such as meteorological observations, radar, and watches/warnings can be overlaid on the display. Ultimately, our goal is to provide a scientifically relevant and easily accessible tool that alerts NWS forecasters to potentially hazardous roadway conditions.

This presentation will highlight the forecast process at Western Region Headquarters, the Google Maps METRo display, and the available forecast information. It will conclude with a brief discussion of how the NWS can leverage this information to work towards the goal of a weather-ready nation.