AAA Texas on Wednesday reported the average price at the pump reached $3.64 per gallon.
Texarkana has the most expensive gasoline statewide at $3.70 per gallon. Drivers in El Paso have the cheapest gasoline in Texas at $3.41 per gallon.
Several refineries in Louisiana and Mississippi closed before Isaac made landfall Tuesday night.
AAA says the hurricane's disruption of Gulf Coast refineries and offshore crude production led to the spike in Texas retail gasoline prices.