NACA® Central - Colorado and New Mexico east of the 107th longitude (which roughly parallels the Rocky Mountains), Kansas, Oklahoma, Missouri, Texas, Arkansas, and Louisiana
NACA® Mid America - Michigan, Indiana, Ohio, West Virginia, Kentucky, and Illinois
NACA® Mid Atlantic - New York, Pennsylvania, New Jersey, Delaware, Maryland, Washington DC (and the surrounding metro area) and the Canadian Province of eastern Ontario
NACA® Northeast - Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, Connecticut, and the Canadian Provinces of New Brunswick and Quebec
NACA® Northern Plains - Montana, Wyoming, Wisconsin, the Upper Peninsula of Michigan, Nebraska, Iowa, Minnesota, North Dakota, South Dakota, and the Canadian Provinces of Alberta, Saskatchewan, Manitoba, and western Ontario
NACA® South - Virginia (south of metro Washington DC), North Carolina, South Carolina, Georgia, Florida, Alabama, Tennessee, Mississippi, and US & British Virgin Islands
NACA® West - Alaska, Hawaii, Washington, Oregon, California, Nevada, Idaho, Arizona, Utah, Colorado, New Mexico, west of the 107th longitude (which roughly parallels the Rocky Mountains) and the Canadian Province of British Columbia