Bay Area drivers are still enjoying the lowest gas prices of the year, even as prices creep back up nationwide. The pump price website GasBuddy finds gas selling as low at two-55 a gallon in Vallejo. That’s the lowest in the Bay Area. In Santa Rosa, the lowest price available is 2.67 a gallon at Rotten Robbie. Triple-A reports the average price for regular nationally is two-26 a gallon, about three cents higher than a week ago.