CHARLESTON, S.C. (WCBD)- The cost of gas in South Carolina has climbed further over the $3 mark in the past week.

The state gas price rose 13.1 cents and South Carolinians can now expect to pay $3.15 per gallon at the pump on average, based on a survey from GasBuddy of 3,028 gas stations across the state.

Gas prices in South Carolina are 12.4 cents per gallon higher than a month ago and stand 89.5 cents per gallon lower than a year ago.

The survey found that the cheapest gas in the state is priced at $2.73 per gallon while the most expensive is $3.89 per gallon, a difference of $1.16 cents per gallon.

The national average price of gas rose by 8.0 cents, averaging $3.44 per gallon today. The national average is 7.1 cents per gallon higher than a month ago and stands at 87.7 cents per gallon lower than a year ago.

“With the transition to more expensive summer gasoline underway coast to coast, wholesale gasoline prices continue to inch up at a rate typical for this time of year, reflected in the national average rising for the second straight week,” Patrick De Haan, head of petroleum analysis at GasBuddy said. “While oil prices edged slightly lower on weaker outlooks for economic growth, continued refinery maintenance and the higher cost of seasonal blends of fuel are offsetting oil’s decline.”

The national average price of diesel fell 4.1 cents in the last week and now stands at $4.30 per gallon.

“The price of diesel, however, continues to slowly decline as we see consumption for diesel lighten up,” De Haan continued. “The best news for both gasoline and diesel prices is how significant a drop we’ve seen from year-ago levels, with more disinflation to come in the weeks ahead, even as gas prices are likely to inch up.”