ROANOKE, Va. (WDBJ/GasBuddy Release) – Average gasoline prices in Roanoke have fallen 2.9 cents per gallon in the last week, averaging $2.84 per gallon Monday, according to GasBuddy’s survey of 155 stations in Roanoke. Prices in Roanoke are 18.3 cents per gallon lower than a month ago and 30.4 cents per gallon lower than a year ago. The national average price of diesel has declined 0.4 cents in the last week and stands at $3.52 per gallon.