Gas prices stayed virtually flat this week as supplies grew, AAA says.

Arizona's statewide average gas price rose about a half-cent in a week to $2.87 per gallon of regular on Friday, while the nationwide average fell fractionally to $2.85.

Tucson kept the lowest average metro price in the state, virtually unchanged at $2.63 per gallon. Flagstaff had the state's priciest gas at $3.07.

AAA says any spike in gas prices related to Hurricane Florence will likely be limited to the East Coast.