CARS.COM — Gas prices jumped 12 cents a gallon nationally the past week — the biggest weekly increase in a year as a tighter supply of gasoline and higher oil prices forced motorists to pay more to fill their tanks. The AAA Daily Fuel Gauge Report showed that the national average for a gallon of regular gas was $1.96, and that the average price was more than $2 in a dozen states and the District of Columbia.
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A month ago, the national average was 25 cents lower and only five states averaged more than $2 a gallon. GasBuddy.com said 30 percent of U.S. gas stations were selling regular for less than $1.50 a month ago, but as of Monday less than 1 percent were at that level.
Several states experienced double-digit increases the past week. Arizona topped them all with an eye-popping 22-cent spike, bringing its statewide average to $1.81, according to AAA. Prices rose 14 cents in Illinois and Mississippi, 15 cents in California, and 18 cents in Nevada and Virginia.
Two weeks ago in Illinois motorists were paying an average of $1.82 for regular, but on Thursday the average was up to $2.05. In Chicago, where taxes are higher, regular gas was averaging $2.32 a gallon and premium $3.13 a gallon. Over the past two weeks average prices have climbed 21 cents in California and Wisconsin, and 26 cents in Nevada.
Prices typically increase at this time of year as gasoline demand rises and refineries conduct seasonal maintenance, temporarily reducing the supply of gas. Despite a recent comeback for oil prices AAA said the seasonal price increases shouldn’t be as severe as in recent years, though some parts of the country could be hit harder than others.
“Prices in some regions may move significantly higher in the near term due to fluctuations in local supply and demand associated with continued maintenance and preparations for summer-blend gasoline in advance of the June 1 deadline for retail facilities to sell the cleaner blend,” AAA stated.
GasBuddy analyst Patrick DeHaan predicted that the national average will soon be more than $2 a gallon and warned that the “jump at the pump” could continue another month or two.
“The national average is likely to rise another 20-55 cents before peaking in April or May, contingent on refineries getting back online and churning out summer gasoline,” DeHaan said in a statement. “In addition, there may be gas price ‘hotspots’ over the next few weeks as there’s little margin for error this time of year as the transition to summer gasoline is made.”
DeHaan doesn’t expect diesel prices to increase as much as gas prices because refineries don’t have to change to a summer blend for diesel; the same requirements apply year round. The national average for diesel increased 5 cents the past week to $2.07 a gallon, 82 cents less than a year ago. In comparison, regular gas is 45 cents cheaper than a year ago and premium, at $2.42, is 40 cents cheaper.
New Jersey had the lowest statewide average for regular gas on Thursday at $1.72 a gallon, followed by South Carolina at $1.73 and Alabama at $1.77. (Prices fluctuate throughout the day and could change.) California had the highest average price for regular, $2.64, followed by Hawaii, $2.56, and Nevada, $2.27.