Gas Prices Are Pointing Lower This Week. However, The Prices Are The Most Expensive For The Month Of March In Four Years, With The National Average $2.53 A Gallon. Tennessee Gas Prices Increased Two Cents Last Week, Before Declining A Penny During The Weekend. Motorists In Tennessee Are Paying On Average $2.32. AAA Auto Club Says Gas Prices Are Typically Volatile During The Spring, With More Ups And Downs Than A Roller Coaster.