SIOUX FALLS, S.D. (KELO)-- Gas prices remain high not just across KELOLAND, but in the U.S. too. The national average for gas is $4.47 a gallon, with diesel at $6.51 a gallon. The average price for gas in South Dakota is slightly higher at 4.26 a gallon. A year ago, the national average price was [. ..] ...read more read less