"Station: NORFOLK INTL AP, VA". U.S. Climate Normals 2020: U.S. Monthly Climate Normals (1991–2020). National Oceanic and Atmospheric Administration. Retrieved May 18, 2021.
Official records for Norfolk kept January 1874 to December 1945 at the Weather Bureau Office in downtown, and at Norfolk Int'l since January 1946. For more information, see Threadex.