(Portland, OR) -- Gas prices have hit their highest levels since last October. Triple-A reports rising crude oil prices are causing gas prices to rise. Crude oil is up nine percent over the last month into the upper 70s and low 80s per barrel. The national average gained four cents to three-86. Oregon's average is up three cents at four-69. Medford has the highest prices at four-80 a gallon and Pendleton has the least expensive gas at four-51. Diesel in Oregon jumped 15 cents to four-76. The national average for diesel increased 12 cents to four-33.