Pampa is a city in Gray County, Texas, United States. The population was 17,994 as of the 2010 census. Pampa is the county seat of Gray County and is the principal city of the Pampa Micropolitan Statistical Area, which includes both Gray and Roberts counties.Pampa hosts the Top 'O Texas Rodeo each year in July, which brings competitors from Texas and the surrounding states to Gray County. The White Deer Land Company Museum, which showcases ranching exhibits, is located in downtown Pampa.