ALEXANDRIA, Va. – April 1 marked a critical date for most retailers across the United States related to summer-blend fuels. An online NACS resource, “Why Prices Historically Go Up in the Spring,” offers more details on the transition season for fuels.

The U.S. Environmental Protection Agency (EPA) defines April to June as the “transition season” for fuel production. Refineries lead this transition and switch over to summer-blend production in March and April. During the annual switchover to summer-blend fuel, which begins in February, gasoline prices historically increase 50 cents per gallon, although they have only increased one cent to $2.65 per gallon, according to U.S. Energy Information Administration weekly data.

Across many areas of the country, refiners and retailers face deadlines to deliver summer-blend fuel. The deadline to sell summer-blend fuel in Southern California was April 1 and Easter Sunday was also the deadline for refiners to produce summer-blend fuel.

“Because U.S. convenience stores sell an estimated 80% of the gasoline purchased, NACS wants to demystify how the market works—from the time crude oil is extracted from the ground to when fuel flows into a consumer’s gas tank,” said NACS Vice President of Strategic Industry Initiatives Jeff Lenard, who helped develop the online resource. “We encourage retailers and other industry stakeholders to share this information with their customers and others concerned about the transition season.”

“Why Prices Historically Go Up in the Spring” and other resources providing an insider’s view on how fuel is produced, refined and ultimately sold at convenience stores across the United States are housed in the NACS Fuels Resource Center.