This week, the national gas price average shed a penny to land at $2.84 per gallon. According to Triple-A Arizona, prices in Arizona have been stable, increasing a fraction of a penny to $2.86. With the switch to winter-blend gasoline taking place this weekend, gas prices are expected to decline even more this month. Triple-A forecasts that the national gas price average will drop to $2.70 this fall and has the potential to drop even more. In Arizona, Tucson has the lowest fuel price at $2.63 per gallon while Flagstaff has the highest at $3.05 per gallon.