Gas prices made a sharp spike overnight, rising by nearly 15 cents in Los Angeles County to an average of $6.108 for a gallon of self-serve regular.
The 14.9-cent increase is LA County's largest since July 14, 2015. The average price per gallon is at its highest amount since July 12.
The average price has risen for 26 consecutive days, increasing 86.2 cents, including 11.9 cents Tuesday and 11 cents Sunday, according to figures from the AAA and Oil Price Information Service. It is 56.3 cents more than one week ago, 82.7 cents higher than one month ago, and $1.699 greater than one year ago.
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The current streak of increases follows a run of 78 decreases in 80 days totaling $1.216. The average price is 35.4 cents less than the record high of $6.462 set June 14.
The average price rose 15.1 cents on July 14, 2015.
Averages remained lower than the prices seen over the summer, when they peaked at a record $6.462 on June 14 in LA County.
The Orange County average price also recorded its largest increase since July 14, 2015, rising 15.5 cents to $6.092, its highest amount since July 9. It has risen 11 of the past 12 days, increasing 70.8 cents, including 10.6 cents Tuesday and 14 cents Sunday. It is 57.2 cents more than one week ago, 90.8 cents more than one month ago, and $1.724 higher than one year ago.
The Orange County average price is 31.8 cents less than the record of $6.41 set on June 12.
The Orange County average price rose 15.7 cents on July 14, 2015.
The average price of a gallon of self-serve regular gasoline in Riverside County has recorded its largest increase since March 9, increasing 14.2 cents to $5.94, its highest amount since July 13. The average price has risen nine consecutive days.
The average price for a gallon of regular statewide is $6.036.
Why are gas prices rising in California?
A series of planned and unplanned refinery maintenance issues tightened fuel supply in California, according to AAA. West Coast fuel inventories are at the lowest level in about a decade, according to Energy Information Administration.
"Until the refineries are fully operational again, supply is going to be tight and will cause pump prices to be volatile," said Doug Shupe, the Automobile Club of Southern California's corporate communications manager.
There may be some relief in November when stations are again allowed to sell winter-blend gas which is cheaper to produce, Shupe told City News Service.
The national average price rose for the eighth consecutive day following a 98-day streak of decreases totaling $1.342, increasing 1.8 cents to $3.765. It has risen 9.1 cents over the past eight days, including 2.2 cents Tuesday.
The national average price is 8.4 cents more than one week ago and 57.8 cents higher than one year ago but 8.8 cents less than one month ago.
The national average price is $1.251 less than the record $5.016 set