A driver fills up at a gasoline pump at a Shell gas station, Oct. 9, 2024, in Seattle. Associated Press File Photo

Gasoline prices have ticked up as the annual springtime increase in demand approaches and refineries begin switching production to summer-blend fuel.

The average price in Western Pennsylvania increased this week by one cent to $3.543 per gallon on Monday, Feb. 17, but is 11 cents lower than it was the week of Feb. 19, 2024, when the average price was $3.655, according to AAA.

In the county, the average price of unleaded, self-service gasoline is $3.578 as of Monday. The state average is $3.366.

The national average price per gallon was $3.16 on Monday. It is about 5 cents higher than a month ago and 12 cents less than a year ago.

“The switch over to summer blend usually starts around now,” said Jim Garrity, of AAA.

He said the transition to summer blend begins on the West Coast and moves east as spring begins.

Refineries’ transition to summer fuel often results in higher prices, according to AAA.

“That’s normal this time of year,” Garrity said.

Most gasoline sold in the country from June 1 to Sept. 15 is summer blend, which has to meet different performance and environmental specifications than gasoline sold in the winter, fall and spring.

The Clean Air Act requires summer gasoline to be less volatile, or less prone to vaporize during high summer temperatures. Summer gas reduces evaporative emissions and ensures optimal engine performance when temperatures are high, according to American Fuel and Petrochemical Manufacturers.

Demand for gasoline has increased slightly, but will increase more beginning in mid-to late-March and continuing in April and May as travel increases, Garrity said.

“Demand is up, but the real uptick starts in the next couple months when the weather improves and road trips are planned,” he said.

AAA cited a report from the U.S. Energy Information Administration, which said demand increased from 8.32 million gallons a day last week to 8.57 million gallons this week, and total domestic supply dropped from 251.1 million barrels to 248.1 million, while gasoline production increased last week to an average of 9.3 million barrels per day.

The worldwide supply of petroleum and other petroleum liquids is expected to increase by 1.9 billion barrels per day this year due mostly to increases in crude oil production in the U.S., Canada, Guyana and Brazil, according to the EIA.

Production from OPEC countries is expected to be 0.1 billion barrels per day due to restraints aimed at stabilizing the oil market, according to the EIA.