A controller is adapted to receive signals indicative of an image including a representation of a posted speed limit for a current section of a road on which an associated vehicle is traveling. The controller evaluates the image to identify the posted speed limit and dynamically determines if the posted speed limit is above a predetermined threshold speed limit. Only if the posted speed limit is above the predetermined threshold speed limit, the controller sets the identified posted speed limit as a warning threshold. If a speed of the associated vehicle is more than a predetermined range over the warning threshold, the controller transmits a warning signal to a notifier for notifying an operator of the associated vehicle and controls a speed of the vehicle based on the posted speed limit.