A method includes configuring a plurality of sub-bounding areas within a primary bounding area. An aggregate traffic message includes traffic information aggregated from the sub-bounding areas and is broadcast throughout the primary bounding area. The roads within the primary bounding area are associated with road classifications, and individual traffic messages associated with those roads are generated. Sub-bounding areas within the primary bounding area are associated with particular road classifications. Individual traffic messages (for particular roads) are selected for inclusion in the aggregate traffic message (broadcast over the primary bounding area) if those messages are associated with a road having a road classification that matches a road classification of a sub-bounding area in which the road is located. The aggregate traffic message is generated by combining the selected individual traffic messages and is transmitted to a station importer.