AP photo

A gas station attendant pumps gasoline in Oregon.

The national average for regular unleaded gas has retreated after 54 consecutive days of increases, according to AAA.

Summer’s gas prices may have peaked this week at a nationwide average of $2.70 a gallon but here in metro Oregon they reached an average of $2.81, with metro Portland seeing $2.99 a gallon.

 Also: Oil prices stabilized

Gas prices had run up for nearly two months straight, regional AAA director Marie Dodds said, but it remained significantly cheaper than pump prices one year ago, when a gallon cost above $4.

The recent retreat comes ahead of the Independence Day travel holiday, after which prices have typically begun to fall.

The price drop-off may be due to a swell in unused U.S. supplies.

Oil prices plummeted ahead of the weekend, dropping to around $69 a barrel.

 Details: Portland Gas Prices

Political turmoil in Iran and Nigeria also continued to put pressure on oil prices. Both countries are major oil producers, and a conflagration in Iran could affect millions of barrels of exports in the Persian Gulf.