In Intelligent Transportation Systems, sensors can be linearly deployed on lanes at an intersection to measure vehicular traffic for an intelligent traffic lights management perspective. Thus, deployed sensors can generate messages periodically containing the number of detected vehicles, or upon the detection of a passing vehicle. In this paper, a theoretical analysis of the two approaches allows us to highlight their performance in terms of the number of messages generated in the network, which is directly related to the energy consumption of sensors. We analyze real data of vehicular traffic at intersections coming from the city of Cologne, and we show that the best message generation strategy depends on the geographical position of the intersection, the lane at the intersection and also on the period of the day. Finally, based on these observations, we propose an adaptive message generation approach. The proposed approach is based on the local measurement of vehicular traffic and considerably reduces the number of messages generated in the network.