What Caused NorCal Gas Prices To Rise 75 Cents Last Month?

(CBS SF) -- The average price of a gallon of unleaded gasoline in Northern California rose by 75 cents in the last month, according to the American Automobile Association's Northern California chapter.

Possible explanations for the increase involve refinery problems and supply issues, including an explosion at ExxonMobil's refinery in Torrance and limited production at Tesoro's refinery in Martinez, according to AAA.

At present, the average price of a gallon of gas in Northern California is $3.37. In the Bay Area, that price is slightly higher at $3.41

The most expensive gas in the region was found in San Mateo, at $3.47 per gallon. The least expensive gas in the region was found in Vallejo, for $3.35.

Statewide, the average price of a gallon of gas is $3.43 - the highest in the country, according to AAA.

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Prices in California are well over the national average of $2.45.

Still, that national average is down $1.04 since this time last year, according to AAA.