Reduced production at West Coast refineries contributed to a weekend "super-spike" in gasoline prices in Santa Rosa and around the state, a California Energy Commission official said Monday.
Such increases are generally short-lived, and prices at the pump should begin to subside in a week to 10 days, said Alison apRoberts, a commission spokeswoman.
The surge pushed a gallon of regular gas to $4.33 in Santa Rosa on Monday, up nearly 13 cents from a week ago, according to the AAA Fuel Gauge Report.
California gasoline prices are typically 20 to 40 cents a gallon higher than the national average, but on Monday Santa Rosa's price was 60 cents above the nation's $3.73 average, the report said.
While gas prices are soaring in California, they are falling in other parts of the country. The national average was down 5 cents from a week ago, and 24 cents lower than a year ago.
Monday's price in Santa Rosa was 7.5 cents higher than it was a year ago.
"It's a West Coast issue," apRoberts said.
Prices are rising in California, in part because of maintenance that curbed production at five of the state's 12 motor gasoline-producing refineries. Those facilities are expected to ramp up production shortly, she said.
Fire closed a BP refinery in Washington in February, and a planned restart failed last week, prompting BP and other companies to buy more expensive gasoline on the spot market, apRoberts said.
A 12-cent price increase, considered a "super-spike," is not unprecedented, she said, but it is hard on consumers.
Last week, the U.S. Energy Information Administration lowered its forecast of the nationwide summertime average price to $3.79 for a gallon of regular gas, 16 cents lower than the forecast in April.
The price of crude oil fell to its low for the year Monday on continued doubts about some European countries' ability to pay off massive government debts.
Benchmark West Texas Intermediate crude lost $1.35 to end the day at $94.78 per barrel in New York, the lowest level since Dec. 19.
The Associated Press contributed to this report.