Charlotte-area drivers are feeling the pinch again at the gas pump as prices continue to soar after the state's fuel tax increased at the beginning of the year and a federal ethanol tax break expired.

Now some are worried prices could go up again based on how oil-rich Iran reacts to new sanctions from the U.S. government.

"North Carolina is getting almost a triple whammy," says Tom Crosby, a spokesman for AAA Carolinas.

Just how bad is it? A regular gallon of unleaded gas averaged $3.60 cents in the Charlotte region on Sunday. That's about 22 cents more than a month ago and up 52 cents from this time last year.

Local gas prices exceed those at the national level, where a gallon of unleaded is averaging $3.48 cents.

Some experts are predicting gas prices could peak at $4.05 this spring before falling toward the end of the year.

For now, the rising fuel prices is causing headaches for some drivers, while encouraging others to continue their regular trips across the South Carolina border to fill up their tanks. The S.C. gas tax is one of the country's lowest, and prices are 20 cents lower than in North Carolina on average, according to AAA.

Stennet Smith of Charlotte began going to Miller's Gas station just over the state line in Fort Mill back in 2009. It's the only station he'll go to, he says, with prices about 30 cents lower than those closer to his home.

Smith used to work near the station, but says he'll still stop by whenever he's in the area to save.

"It's worth it," he says.

Miller's Gas added eight gas pumps in December to help deal with the overflow in traffic from North Carolina drivers and visitors to a flea market next door, said manager Patricia Pasternak. She said the station averages about 15 to 20 calls a day from folks curious about the price of gas.

Richard Szymanski lives about eight miles away from Miller's, but says the lower price and newer gas pumps - which he says means less water in the fuel - draws him to the station.

Still, while gas prices may feel uncomfortable now, some worry they could only go higher in the coming weeks.

One of the problems, Crosby said, is uncertainty about what'll happen in Iran and if there will be a disruption in the oil supply. He said speculators who are buying oil futures are betting there will be a crimp in the supply.

"If they win," he says, "all the motorists lose."

In a recent report, Tom Kloza of the Oil Price Information Service, predicted fuel prices could peak at $4.05 sometime this spring. He said prices could rise above $4 in April, a time when they usually increase.

He doesn't expect prices above $4 a gallon to become the "new normal," however. In a recent report, OPIS predicted gas prices will eventually fall short of last year's average price of $3.51 a gallon.

Kloza discounted the possibility of a major shock, such as Iran closing the Straits of Hormuz or another war.

"That's about the only way you get to $5 to $6 a gallon predictions," he said of such unlikely events.

Some of that "worry premium" is already included in the price of oil, Kloza said.

"If you woke up tomorrow and found that Israeli warplanes were bombing (Iran), there would be an incredible spike," Kloza said. "But I think it would be like a fever" and subside eventually, he said.

The U.S. fleet is more efficient, with people more ready to adopt alternate forms of transportation in the event of a major increase in oil prices, than 10 years ago, he said. Staff writer Ely Portillo contributed.