Concepts for Managing Freeway Operations during Weather Events

The goal of this research was to help the Texas Department of Transportation (TxDOT) develop a structured, systematic approach for managing traffic during weather events. The focus in this research project was on common weather events – such as fog, high winds, heavy rains, and snow and ice storms – that impact traffic operations day-to-day. First, the authors conducted a survey of selected TxDOT districts to determine what information traffic management center (TMC) operators need to manage traffic operations during weather events. Through a review of the existing literature, the authors assessed systems and technologies that other states have deployed to manage traffic during weather-related events. They reviewed the current state of weather-related detection and monitoring technologies. Using historical traffic detector and weather information, they assessed the magnitude of the impact of different weather events on traffic operations. Using all this information, the authors developed concepts of operations for how TMC operators should respond to different types of weather-related events, including limited visibility conditions, ponding and flash flooding, high winds, severe thunderstorms, tornados, and winter storms. They developed a catalog of advisory, control, and treatment strategies (or ACTS) that operators could use to manage traffic operations during weather events. Specific criteria outline when TxDOT TMC operators should implement different types of responses. The authors proposed messages that TxDOT TMC operators can use on dynamic message signs (DMSs) to achieve different advisory and control strategies for different types of weather events. Finally, the authors provided a framework that TxDOT can use to integrate weather information from the National Weather Service and other private weather providers into its TMC operations software.