The national average price of a gallon of unleaded gasoline increased 1 cent to $2.88 for the week ending July 16 and has climbed 3 cents since the Fourth of July holiday, according to AAA.

The July 16 price level is 2 cents cheaper than a month ago and 63 cents more expensive than a year ago. For the week, several states including Delaware, Florida, and Michigan have seen an increase of nearly 10 cents

"Typically during July, gas prices have a tendency to trend cheaper," said Jeanette Casselano, AAA spokesperson. "However, with crude oil prices nearly $25 more a barrel compared to last year, we are seeing an upward pricing trend. If this trend continues, and if we see any supply disruptions, such as a hurricane, pump prices may see new three-year highs."

States with the highest fluctuation over the past month include New Mexico (down 12 cents), Ohio (up 11 cents), Arizona (down 10 cents), Nevada (down 10 cents), Delaware (up 8 cents), and Texas (down 8 cents). States with the least expensive gas include Alabama ($2.55), Mississippi ($2.56), South Carolina ($2.57), Louisiana ($2.60), and Arkansas ($2.60).

Meanwhile, the average price of a gallon of diesel has fallen four-tenths of a cent to $3.239, which is 74.8 cents higher than a year ago, according to the U.S. Energy Information Administration.

Related: Controlling Fuel Costs as Gas Prices Rise