On Oct. 7, the average California regular retail gasoline price surpassed $4 a gallon for the second time since 2014. Prices fell after refiners in the state assumed normal operations, according to a report by the U.S. Energy Information Administration. The last time California gasoline prices reached $4 a gallon was in May 2019, which was a result of planned and unplanned refinery outages in California.  California’s petroleum markets are isolated from the rest of the U.S. because of California's lack of petroleum infrastructure connections to the rest of the country, so unplanned refinery outages in the state can have larger price impacts than in other areas of the country. In addition, California requires a different gasoline specification than the rest of the country, further narrowing supply options. Click for article