Gas prices reached their highest level in California in five years, some stations in Los Angeles are charging more than $5 a gallon.

A gallon of self-serve regular gasoline reached an average of $4.25 in Los Angeles County Wednesday, Oct. 9, the AAA and Oil Price Information Service reported. It has risen 86.4 cents since the start of the year.

California motorists still pay the most for gas in the country, with the cost of about $1.54 higher than the national average.

AAA spokeswoman Jeanette Casselano said in a statement that refinery Los Angeles-area outages are a major factor for the recent surge in pump prices. These unexpected events crimped California’s fuel supply, according to KTLA.

“All regions are seeing planned and unplanned refinery maintenance, but it is only the West Coast that is really seeing gasoline stocks tighten and gas prices increase,” Jeanette said in a news release on Monday, Oct. 7.

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, according to FOX 13 News.