SAN FRANCISCO (CBS/AP) — California gas prices finally have begun to fall after a month that saw them surging by nearly 50 cents a gallon—but a continuing refinery shutdown may keep supplies short.

The AAA Daily Fuel Gauge Report says the average price of regular Wednesday is less than $4.67 a gallon, down a half-cent from Tuesday. It’s still the highest price in the nation, however.

The top average price in the state is $4.75 a gallon in the San Luis Obispo area.

State officials predicted prices would fall after Gov. Jerry Brown ordered early production of a winter fuel blend to replace costlier summer blends.

The spike was partly driven by an August fire that partially closed a Richmond refinery. Chevron says it will remain closed through December.

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