Next generation vehicular communication environment will consist of heterogeneous Radio Access Networks (RAN). For seamless connectivity, vertical handover is a mandatory requirement. A novel context aware vertical handover algorithm is presented here. TOPSIS (Technique for Order Preference by Similarity to Ideal Solution), which is a Multi Criteria Decision Making (MCDM) tool, is used for the development of algorithm and MATLAB/SIMULINK is used as simulation platform. The optimum network is selected, based on multiple factors such as network traffic load, velocity of mobile station, data rate, usage cost and initial delay of network, among the available networks such as WiMax, WLAN and UMTS. This algorithm has been tested by simulating a virtual road traffic scenario.