Gasoline prices have been on the rise nationally, with the West Coast seeing the largest increases over the past month. Now, drivers in New England states are likely to see an outsized spike at the pump.
This week, New York, New Jersey, Pennsylvania, and other Northeastern states switched to a more expensive summer blend of gasoline, sending wholesale prices $0.30 to $0.32 per gallon higher, said Tom Kloza, global head of energy analysis at OPIS.
"These increases will make their way to the street in the remainder of the week," Kloza told Yahoo Finance. "This region will see lots of stiff increases that take consumers by surprise."
Kloza noted that the rest of the country has already switched to summer gas blends. He expects drivers will see retail prices peak as soon as this weekend before starting to cool off in some areas.
On Thursday, the national average for gasoline sat at $3.67 per gallon, roughly a penny less than a year ago, according to AAA data.
One area that recently saw an outsized move higher is California, where high taxes and regulations on gasoline traditionally keep prices well above the national average.
The Golden State's average sat at $5.45 on Thursday, $0.54 higher than one year ago.
"The latest West Coast price increases are due to California refinery outages, both scheduled and unscheduled," said Andy Lipow, president of Lipow Oil Associates, earlier this week.
California also provides refined fuel for nearby Nevada, sending that state average up to $4.63, roughly $0.35 higher than a year ago.
Oil's year-to-date move to the upside has exacerbated upward pressure on prices in recent months.
Over a one-month period, US crude rose from $78 to $85 per barrel, accounting for an increase of about $0.17 per gallon of gasoline, according to Lipow Oil Associates.
On Wednesday, West Texas Intermediate (CL=F) futures closed below $83 per barrel, while Brent (BZ=F), the international benchmark price, settled below the $88 level.
Ines Ferre is a senior business reporter for Yahoo Finance. Follow her on Twitter at @ines_ferre.
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