Gas prices around Abilene Thursday were about $3.69 per gallon.
Retail gasoline prices across the state have jumped 21 cents in the past week as U.S. refineries prepare to switch to a more expensive summer-blend gas.
The state average for gas is $3.64 per gallon for regular.
The nationwide average price of gasoline rose 15 cents this week. It's now at $3.78 per gallon.
AAA said the updated gasoline blend is expected to reach markets in a couple of weeks but until then prices at the pump could continue to rise.