Many Northwest Indiana residents are complaining gas prices are too high after they raced to nearly $4 a gallon.
Gas prices have shot up by 15 cents a gallon since Wednesday, and by nearly 28 cents a gallon over the last two weeks. The average price is now $3.91 per gallon in the Gary metropolitan area, according to GasBuddy's daily survey of 314 gas outlets in Gary.
Northwest Indiana residents are paying more at the pump than the national average of $3.64 per gallon, but not as much as Hawaiians, who are paying a U.S. high of $4.36 per gallon.
Analysts have attributed the sudden hike to an outage at a Marathon refinery in Louisiana that was shut down after a tornado.
"It's supply-driven, not demand-driven," said Purdue University energy economist Wally Tyner.
Gas likely just hit the highest point it will reach all summer, unless there are more refinery or pipeline issues. Prices will likely start to come down next week, and potentially reach as low as $3.50 a gallon by the end of summer.
"Any time there's a supply disruption, prices shoot up really quick but come down slower," he said. "But I'm guessing this is a temporary supply problem that can be worked out in the next week."
Gas prices in Northwest Indiana were well over $4 a gallon at the same time last year, because of production disruptions at four refineries, including the BP Whiting Refinery. But production levels have since been restored, and gas prices should likely range between $3.45 and $3.90 per gallon in Indiana during this summer's travel season.
Tyner estimates that gas prices will be about 6 cents higher on average this summer, because crude oil prices have been holding at more than $100 a barrel.