A Metropolitan Planning Area (MPA) is the geographic area determined by agreement between the Metropolitan Planning Organization (MPO) for the area and the Governor, in which the metropolitan transportation planning process is carried out. MPO planning area boundaries are established according to the federal metropolitan planning regulations (23 CFR 450, Subpart C)
http://www.gpo.gov/fdsys/pkg/FR-2007-02-14/pdf/07-493.pdf. The MPA must encompass at a minimum the Census Urbanized Area and the contiguous geographic area likely to become urbanized within the next 20 years. This data was constructed from the NYS civil boundary files that are owned and maintained by the New York State Office of Cyber Security & Critical Infrastructure Coordination (CSCIC). Federal regulation requires that states designate MPOs in Census Urbanized Areas with populations of 50,000 or more. MPOs are responsible for ensuring that federal-aid transportation projects in the metropolitan area result from a continuing, comprehensive and cooperative transportation planning process. New York State has thirteen MPOs.