U.S. gasoline prices are on a steady climb, though they may be peaking as refineries complete seasonal turnover work, motor club AAA reports.

AAA reports a national average retail price for Tuesday at $2.75 for a gallon of regular unleaded, up a fraction of a percent from Monday but nearly 6 percent above the price one month ago.

"Gas prices surged this spring due to a rally in crude oil prices from multi-year lows, seasonal refinery maintenance, the changeover to summer-blend gasoline and domestic refinery issues that have impacted regional production," the motor club said in its weekly status report.

Several states in the country reported gasoline prices below the $2 per gallon mark in late 2014 and early 2015. Five states in the Lower 48 now report gas above the $3 mark and the national average is the highest it's been so far this year.

Midwest states are experiencing increases in part because of refinery problems in Ohio and Illinois. Two of those refineries, Exxon Mobil's facility in Joliet, Ill., and Citgo's refinery in Lemont, Ill., are both running at reduced capacity.

Refineries are producing a summer blend of gasoline, which is more expensive to produce because of additional environmental safeguards for air quality at higher temperature.

The motor club said there's a "good chance" that retail gasoline prices will start to fall off as refineries finish their maintenance. This summer, AAA said, may be the cheapest for gas since 2009.

AAA spokesman Avery Ash said gas prices went up this spring faster than expected, though drivers should consider the price for a gallon of gas this time last year was $3.67 per gallon.

"This could be the year of the summer road trip with lower gas prices motivating millions of people to travel," he said in a statement. "Many drivers are likely to save hundreds of dollars this summer as gas prices remain more affordable than in recent years."