Motorists hitting the road to celebrate the July 4 holiday will be feeling more pinched than last year, shelling out an average of $2.90 per gallon, the highest Independence Day prices since 2014, when the national average hit $3.66 per gallon, according to GasBuddy, a smartphone app connecting drivers with gas stop locations and prices. Making holiday travel sourer this year is that a price jump is looming.