(CBS SF) – Bay Area gas prices have plunged in the past month and are expected to drop even further with the approach of autumn, according to AAA’s latest gas survey released Tuesday.

The average price per gallon in the Bay Area is currently $3.13, down 25 cents from the previous month.

In the Bay Area, Fremont gas prices decreased the most by 41 cents from last month, now costing $3.01 per gallon. Concord maintains the lowest gas prices in the region at $3.00 per gallon, according to the AAA survey.

San Francisco experienced the region’s smallest monthly decrease in gas prices at 20 cents, and has consistently been home to the highest gas prices in the Bay Area. Gas in San Francisco now costs about $3.27 per gallon, according to the survey.

Findings of the AAA survey also indicated that Labor Day weekend gas prices were the lowest they have been at that time of year in more than a decade.

AAA Northern California spokeswoman Cynthia Harris credits the drop in gas prices to “an oversupply of crude oil” and record highs in refinery output.

Harris expects that this is not the end of the declining gas prices.

“Nationwide, prices are expected to continue to drop through the fall,” Harris said in a statement. “This expectation is contingent upon the price of crude oil remaining relatively low and refineries being able to perform routine maintenance as they switch to the lower cost winter formulation.”

According to AAA, every Sept. 16 refineries in many parts of the country switch over to a winter blend of gasoline that is less expensive than the summer blend.

The summer blend of gasoline is required by the U.S. Environmental Protection Agency in some regions in order to address air quality issues during the summer months, according to AAA.

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