Every time motorists have pulled up to the pump in recent days, they have noticed a surge in gas prices. The statewide average is now $3.58 a gallon, 18 cents higher than it was just a week ago.

Drivers may be wondering: Is that increase due to another wave of inflation, turmoil in the Middle East, the war in Ukraine?

Mark Shieldrop of AAA says many of those factors are already baked into oil and gas futures, and that the cost of gasoline has been slowly increasing since the beginning of the year. The recent surge in price, he said, is due entirely to the annual reformulation of gas that produces “summer blend” — a gas with additives that reduce evaporation and results in less air pollution and smog. It’s a more expensive refining process, which is why prices go up every summer.

“Most years, the price difference between winter and summer blend is anywhere from 5 to maybe 10 cents a gallon,” he said. “This year the price difference was significant: It was 30 cents. So that’s why we saw a pretty big spike in gas prices over the past week.”

Shieldrop says the price increases historically continue through June, and the price could continue to rise to near $4 a gallon. But, as summer begins to wane, so do the price increases.

Although prices are sensitive to world events, Shieldrop says he doesn't expect them to influence U.S. prices at the pump.

“If we start to see oil approach $100 a barrel, then certainly we're going to see an impact at the pump based on that. But right now, we're not seeing a huge impact,” he explained. “And I think what's going on is the United States, we're producing so much oil here in our country. And we're the world's largest producer of oil and gas at this point. So we're less vulnerable to geopolitical issues than maybe we would have been ten, 15 years ago.”

But things could always change. Shieldrop is the first to admit that it is difficult to accurately predict future oil and gas prices because so many factors are at play.