The average price of a gallon of self-serve regular gasoline in Los Angeles County rose Tuesday to its highest amount since Aug. 6, 2015, increasing 2.3 cents to $3.911.

The average price has risen 30 consecutive days, increasing 55.2 cents, including 2.2 cents on Monday, according to figures from the AAA and OPIS. It is 22 cents more than one week ago, 55.2 cents higher than one month ago and 33.2 cents greater than one year ago.

The Orange County average price also rose to its highest amount since 2015, increasing 2.4 cents to $3.875. It has risen 22 consecutive days, increasing 55.3 cents, including 2 cents on Monday.

The recent sharp increases are the result of a series of refinery issues that have reduced supply, according to Jeffrey Spring, the Automobile Club of Southern California's corporate communications manager.

"Of the 10 California refineries that produce at least 75,000 barrels of fuel a day, six of them are experiencing unplanned issues, planned maintenance or both," Marie Montgomery of the Automobile Club of Southern California told City News Service.