California drivers are once again paying for the most expensive gas in the nation and will continue to experience price swings in the near future, due to statewide refinery issues.

According to the latest AAA Fuel Gauge Report, pump prices are up $0.17 with the average price of unleaded regular at $2.85 per gallon as of today.

The least expensive fuel can be found in Marysville, where the average price for a gallon of regular is $2.44. The highest price is in San Francisco, where the average price is $2.826 a gallon, up $0.06 from the last AAA gas survey.

“California continues to weather ongoing refinery issues and remains the most expensive state for gasoline,” said Cynthia Harris, AAA Northern California spokesperson. “California ranks third in the nation in refining capacity and refineries in the state typically operate at higher-than-average levels to meet demane.”

Disruptions in gas production generally lead to noticeable spikes in the price at the pump, which are often exacerbated due to the market’s relative isolation and specific fuel requirements.

Consumers in the region will likely experience price swings in the near term due to both planned and unplanned maintenance, and this could increase the national average price of gas even as prices drop in other parts of the country.

Nationally, prices has decreased in 45 states and continue to drop to multi-year lows, with today’s average price of $1.96 per gallon representing the cheapest average price at the pump since March 23, 2009.

Both oil benchmarks have posted losses for every day of trading in 2016, and as a result, closed out the week at lows unseen in more than a decade.

Expectations that prices will continue to hover at multi-year lows are beginning to surface and market watchers are paying close attention to both China and the Middle East.

Growth in China’s economy was once seen as a factor that could offset some of the market’s imbalance, though there is more uncertainty now that concerns over its economy continue to grow.

West Texas Intermediate (WTI) closed out Friday’s formal trading session on the NYMEX down 11 cents, settling at $33.16 per barrel.

This represents a loss of approximately 10 percent on the week and was the benchmark’s lowest settlement since Feb. 9, 2004.