"Station: Pierre RGNL AP, SD". U.S. Climate Normals 2020: U.S. Monthly Climate Normals (1991-2020). National Oceanic and Atmospheric Administration. Archived from the original on July 3, 2023. Retrieved October 13, 2021.
"Station: Pierre RGNL AP, SD". U.S. Climate Normals 2020: U.S. Monthly Climate Normals (1991-2020). National Oceanic and Atmospheric Administration. Archived from the original on July 3, 2023. Retrieved October 13, 2021.