The average price of a gallon of self-serve regular gasoline in Riverside County rose Monday for the 20th time in 22 days, increasing six-tenths of a cent to $4.18, its highest amount since July 21, 2015.
The average price has increased 59.8 cents over the past 22 days, including a half-cent Sunday, according to figures from the AAA and Oil Price Information Service. It is 15.2 cents more than one week ago, 58.9 cents higher than one month ago and 39.8 cents greater than one year ago.
The average price has risen 91.2 cents since the start of the year.
The 2015 figure included stations in San Bernardino County.
Gas prices began increasing rapidly last month after Saudi Arabia oil production facilities were attacked, and the increases sharpened after three Los Angeles-area refineries slowed or halted production due to maintenance issues and no imported gasoline was available to make up for the shortfall, according to Jeffrey Spring, the Automobile Club of Southern California’s corporate communications manager.
Local refineries had already cut back production of summer blend gasoline in anticipation of switching to selling the winter blend beginning Nov. 1, creating even more of a shortage.