1. A method comprising: receiving sensor data representing traffic patterns from one or more sensors; identifying holiday traffic data from the sensor data, the holiday traffic data associated with multiple repeating time epochs for multiple holidays; calculating a plurality of clusters for the holiday traffic data, wherein at least one of the plurality of clusters is defined by a variable centroid; identifying a dominant traffic pattern cluster from the plurality of clusters; and storing the dominant traffic pattern cluster in a traffic prediction model, wherein a road layout or a traffic signal pattern is tested using simulated traffic data generated from the traffic prediction model and the dominant traffic pattern cluster.