Usability Evaluation of Mobile Weather Hazard Alert Applications

Cell phones enable us to receive and respond to critical incidents, such as: severe storms, tornadoes, and flash floods. However, due to the small display size of cell phones, and regardless of simplified symbols or alert messages, it is possible to overlook users’ ability to interact with the available features and understand the messages in a timely manner. Untrained and trained users of the Weather Radio application participated in an experiment to perform three search tasks; (task 1: location search, task 2: alert settings, and task 3: map settings). In task 4, they evaluated two types of weather alert messages: original National Weather Service (NWS) messages vs. filtered (proposed) messages. By recording users’ completion time on the search tasks, the results showed that the time of the typing in text bar method for task 1 was significantly less than the pin on map method, while much more time was required to complete tasks 2 and 3 by the untrained users compared to the trained users. It was also revealed that the proposed messages were more effective than the original messages by both user groups. This research of user-centered designs provides a foundation to support the designs of time-critical mobile alert systems.