The national average price of regular unleaded has reached $2.87 per gallon, which is the most expensive gasoline price since 2014, according to AAA. The price is 1 cent more than a week ago, the same price as a month ago, and 52 cents more than a year ago.

The price surge is coming as gasoline demand nears an all-time high at 9.88 million barrels for the past week. Gasoline inventories fell to 231 million barrels at the end of July from 240 million barrels at the end of June, according to the U.S. Energy Information Administration.

"We are likely going to see an end of summer pump price rally as inventories continue to tighten, especially on the East Coast," said Jeanette Casselano, AAA spokesperson. "This week's EIA demand and inventory reports will give further indication of how much higher the national gas price average could jump before summer is over."

States with the most expensive gasoline now include Hawaii ($3.76), California ($3.62), Washington ($3.40), Alaska ($3.37), Oregon ($3.28), Nevada ($3.20), Idaho ($3.15), Utah ($3.08), Connecticut ($3.07), and Pennsylvania ($3.06).

States with the largest monthly changes include New Mexico (down 11 cents), Arizona (down 10 cents), Delaware (up 9 cents), Utah (down 7 cents), South Carolina (up 6 cents), Georgia (up 5 cents), Nevada (down 5 cents), Colorado (down 5 cents), Kentucky (down 5 cents), and Alabama (up 4 cents).

Meanwhile, the price of diesel has fallen three-tenths of a cent to $3.223, which is 64.2 cents higher than a year ago, according to the EIA.