The nation's average gasoline price increased 2 cents to $2.86 for the week ending July 30, as supply declined amid increased summer driving demand, according to AAA.

Overall crude inventories fell to 405 million barrels over the past week, which is about 80 million barrels less than the same time a year ago, according to a reprt from the U.S. Energy Information Administration. The current price level is 1 cent lower than a month ago and 55 cents higher than a year ago. In the past year, crude oil prices have increased by about $20 per barrel.

"As crude and gasoline inventories tighten, motorists can expect gas prices to trend higher and remain volatile," said Jeanette Casselano, AAA spokesperson. "On the week, pump prices increased as much as 11 cents for some states with others seeing decreases of up to 4 cents."

States with the most expensive average gasoline price include Hawaii ($3.78), California ($3.62), Washington ($3.40), Alaska ($3.37), Oregon ($3.29), Nevada ($3.20), Idaho ($3.11), Utah ($3.09), and Connecticut ($3.07).

States with the largest weekly changes include Michigan (up 11 cents), Indiana (up 9 cents), Ohio (up 8 cents), Kentucky (up 6 cents), Illinois (up 4 cents), Kansas (up 4 cents), Delaware (down 4 cents), New Mexico (down 3 cents), West Virginia (up 3 cents), and South Carolina (up 3 cents).

Meanwhile, the average price of a gallon of diesel increased six-tenths of a cent to $3.226, which is 69.5 cents higher than a year ago.

Related: Controlling Fuel Costs as Gas Prices Rise