Currently, there are no all-inclusive methods for visual analysis of ensemble vector fields (EVF) that provide identification of flow trends and general flow similarity over the full extent of transport across ensemble members. Finite-time Variance Analysis (FTVA) provides flow structure information only on particle distributions at the termination of streamline integration. In this paper, we first present a flow structure based on streamline clustering. Second, we discuss a method using streamline clustering to provide information of flow coherence at corresponding spatial regions in the EVF. We consider the regions where bifurcation in flow trends among the EVF members occur. We will also discuss how both methods can be used as a sequential framework for EVF analysis, by using the results of the scalar flow structure to find regions of member flow dissimilarity for further analysis.