SAN FRANCISCO (CBS/AP) — Californians woke up to sticker shock Friday as overnight gasoline prices jumped by up to 20 cents a gallon in some areas, prompting some stations to close and others to charge more than $5 a gallon.

The AAA Daily Fuel Gauge report says the average price of gas across the state was nearly $4.49 a gallon—highest in the nation.

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In Southern California, the price jumped 20 cents a gallon to $4.53 in Ventura and 19 cents to nearly $4.54 in the Los Angeles-Long Beach area.

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In San Francisco, a gallon of regular gas is nearly $4.60. In many areas, prices have jumped 40 cents in a week.

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Refinery problems have helped send wholesale prices soaring.

Some stations ran out of gas and closed Thursday rather than pay those costs. The Los Angeles Times ( says some Costco stations closed.

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