CARS.COM — Gas prices are on the rise again, with the biggest increases in the Great Lakes area, and they are following a typical late-winter pattern brought on by seasonal refinery maintenance that reduces production and a pending switch to summer gasoline blends. The AAA Daily Fuel Gauge Report on Thursday said that the national average for regular gas was $2.31 a gallon, up 3 cents from a week ago. Premium gas was up 2 cents to $2.83, and diesel fuel was steady at $2.52.
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Pump prices were stable through much of February but started to inch up this week. AAA said motorists should expect prices to keep climbing in the coming weeks.
“In mid-March, prices will likely rise as more refiners begin to switch from winter-blend to summer-blend gasoline and driver demand increases,” AAA said in a statement.
While gasoline production slows because of refinery maintenance and the change to summer gas, Patrick DeHaan, senior analyst for GasBuddy.com, said that increases the risks that mishaps at refineries could cause price spikes.
“Unexpected refinery outages could cause additional volatility or spikes in prices over the next two months due to the limited ability for other refiners to help offset any production losses while performing their planned maintenance,” DeHaan said in a blog post.
On the West Coast, where AAA said a fire at one refinery in California and production issues at another crimped the gasoline supply, prices rose by 3 cents or more. California saw prices rise by 7 cents to a statewide average of $2.97 a gallon, and a growing number of stations in the Los Angeles and San Francisco metropolitan areas were charging more than $3 a gallon for regular.
Motorists in the Great Lakes area, where prices tend to be the most volatile, also saw significant increases the past week. Average prices for regular climbed 6 cents a gallon in Illinois, 7 cents in Ohio and 10 cents in Indiana and Michigan. The average price in Kentucky rose 8 cents.
Indiana had some of the lowest pump prices three weeks ago, but the average has jumped by 21 cents since then to $2.30 a gallon. In neighboring Ohio, prices have shot up by 22 cents the past three weeks to $2.24 and in Michigan by 25 cents to $2.44.
Hawaii had the highest average for regular, $3.09, and Alaska and Washington, at $2.77, were the next highest after California, according to AAA. (Prices fluctuate throughout the day and could change.)
South Carolina had the lowest average for regular, at $2.06 a gallon, followed by Alabama, $2.07; Tennessee, $2.08; and Mississippi, $2.09. Prices rose by 1 to 4 cents in most parts of the Southeast and Southwest the past week.