As the weather in the U.S. begins to cool down, diesel and gas prices are only going up. The national average on-highway diesel price rose 3 cents to $3.766, according to data released by the U.S. Energy Information Administration (EIA) on September 8. Gas prices rose 2 cents to $3.192. What are the current diesel prices across the U.S.? Here are this week’s diesel price highlights from each region of the U.S.: