SAN FRANCISCO (KGO) -- If you haven't already experienced it, brace yourself for $4 gas prices. According to gasbuddy.com, prices are surging.
On Tuesday, the average gas price in California was $3.86 for a gallon of regular.
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In San Francisco, the average price was seven cents higher-- at $3.93 a gallon.
In Oakland, the average price was $3.86 per gallon, the same as the state average.
In San Jose, the average price was $3.87 per gallon.
"Four days ago we filled up and it was 20 cents cheaper," said Kevin Curioso, who lives in the East Bay and drives for a living.
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Curioso was right on the money. California gas prices have jumped up 22 cents in the past week and 53 cents in the past 30 days.
"I have to work harder to fill up my personal car," said Curioso.
Plenty of gas stations in San Francisco already have prices well over $4. The Shell Station at 5th and Folsom Streets was selling a gallon of regular for $4.49 a gallon.
"Several refineries, which began almost a month ago, began experiencing hiccups," said Dan McTeague, who is a petroleum analyst for Gas Buddy. He says maintenance problems at four California refineries are to blame, including the Valero refinery in Benicia.
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Two weeks ago, the Benicia refinery temporarily shut down when a gas scrubber malfunctioned, sending black smoke into the air. The refinery was slapped with 12 violations from the Bay Area air quality management district, for visible emissions and creating a public nuisance.
"I haven't seen this since the Exxon Mobile plant exploded in Torrance back in 2016, so we're seeing quite a run on supplies and that's really what is causing these prices to dial up," said McTeague, who thinks gas prices will continue to go up for at least the next few weeks.
Refineries to blame for surging California Gas Prices