Taking that affordable summer road trip—or just driving around town for errands—might suddenly be a budget buster, due to rising gas prices.
On Monday, the national average for a gallon of regular unleaded gasoline hit $3.61, according to AAA. That's up 14 cents from a week ago, and the largest price spike since February, said AAA spokesman Michael Green.
Worse, analysts expect prices could go even higher, edging up another 5 to 15 cents per gallon before the end of July.
"Crude oil prices are up 10 percent in last three weeks, and gas prices have some catching up to do," said Patrick DeHaan, senior petroleum analyst for GasBuddy.com. "When oil prices are up, gasoline is bound to follow."
Several other factors have also played a role. Crude prices have trended higher on news of minor production problems at several U.S.refineries, as well as continued violence in Egypt. "That spooks the market," Green said. News on either issue could push prices higher, or lower if the news points to increased supply.
Prices aren't likely to settle before Labor Day, or even September. "The 500-pound gorilla that's ready to walk in the door is the upcoming peak of hurricane season" in August, said DeHaan. After Hurricane Katrina damaged refineries in the Gulf of Mexico in 2005, spiking prices and stretching supply, major storms moving in that direction generate worries of similar problems. That can also edge crude prices higher.
That said, drivers in most states won't see prices top $4 per gallon, Green said. (On Tuesday, just three—Alaska, California and Hawaii—had prices surpassing that mark.)
Strategies abound for drivers to cut their pain at the pump.The U.S. Department of Energy's FuelEconomy.gov recommends strategies including observing the speed limit (saving 7 to 14 percent), and clearing extra items from your vehicle (1 to 2 percent savings per 100 pounds).
But the best recourse for drivers, experts say, is to assess local prices before filling up. "When prices are volatile, that can mean a wider gap between the cheapest and most expensive stations," said DeHaan. Per-gallon savings could be as much as 70 cents just by choosing one gas station over another.
Apps like GasBuddy and AAA TripTik display local prices,helping drivers determine which stations in an area are cheapest. (Some sites and apps rely on users to submit new prices; check when a price was submitted before banking on it as the best savings.)
Pair that with the right payment method. Some gas stations offer savings of roughly 5 cents per gallon for paying with cash. Convenience store chain Cumberland Farms launched a payment app in January offering discounts of 5 to 10 cents per gallon for users.
Plenty of credit cards also offer generous rewards on gas purchases, said Odysseas Papadimitriou, chief executive of comparison site CardHub.com. Look for a general rewards card rather than one tied to a specific station, which lets drivers shop around. General cards are also less apt to cap rewards earned, making them more generous than station-specific cards when prices are rising, he said.
CardHub.com's top pick is the PenFed Platinum Rewards card, which offers 5 percent cash back on gas purchases. Cardholders must be members of the credit union, but can sign up for as little as $15.
Supermarket loyalty programs may offer another avenue for savings. Although memberships in such programs fell 1 percent since 2010, according to research firm Colloquy, chains have added more gas discounts based on grocery purchases. In some cases, shoppers can earn vouchers for more than $1 off per gallon on a single fill-up, based on something they would do anyway—buy groceries.
—By CNBC.com's Kelli B. Grant. Follow her on Twitter @KelliGrant.