The Niagara Frontier is a large region in several states. It is one of the regions New York State is commonly broken up into. Quite literally it is the land along the Niagara River and south shores of Lake Erie. It is part of the region known as Western New York and Upstate New York. The portion of Ontario just across the Niagara River is known as the Niagara Peninsula.
The National Weather Service office in Buffalo currently defines the Niagara Frontier as the following: Erie County, New York north of US 20 - includes Buffalo, New York Niagara County - includes Niagara Falls, New York Orleans County Genesee County