SAN DIEGO — If you’re hitting the roads for Thanksgiving this week, expect plenty of company. AAA is predicting one million more Americans will drive for the holiday this year compared to 2018. And when it comes to gas prices, some in San Diego are experiencing sticker shock.  

AAA predicts more than 55 million Americans will travel this Thanksgiving. One of the top destinations is Southern California where we're seeing some of the highest gas prices in the nation. 

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Local prices topped $4 a gallon a few months ago. Since then they've backed off thanks to the seasonal change to a cheaper blend of gas, but we're paying about 26 cents more a gallon than a year ago. 

Part of it comes down to supply and demand. Supply is tighter thanks to processing issues. 

Southern California has been marred with refinery issues and power outages in late summer that shut some refineries down temporarily.  

Prices are about 70 cents more than two years ago. 

That was well before SB 1, which added to the gas tax. The American Petroleum Institute estimates those in Southern California pay more than 80 cents in taxes for every gallon.  

Voters decided to keep the latest taxes during the last election, but it doesn't account for all of the higher prices. Some Californians think companies are deliberately inflating the cost of gas. 

Governor Gavin Newsom recently asked the attorney general to investigate whether big oil companies are price fixing. 

Still, prices don't seem high enough to keep most drivers off the road this Thanksgiving.