The surge in gasoline prices has stalled around $3.92 per gallon, but experts caution that more increases are coming.
Many refineries still haven't undergone a seasonal maintenance period that will force them to produce less gas. That will tighten supplies in some parts of the country, especially in the Great Lakes region, and push prices higher.
"In about two weeks we're going to see more refineries go into maintenance, and prices are going to creep up," said Patrick DeHaan, a retail price expert with GasBuddy.com. DeHaan expects the national average to rise to between $3.95 and $4.35 per gallon by the end of April.
Gas prices have been steady in the past week, with the national average adding just over a penny per gallon, according to AAA, Wright Express and Oil Price Information Service. At one point during the winter, the average rose on 39 out of 40 days. It's up 65 cents since Jan. 1.
Current stable prices will be temporary, DeHaan said. Refineries schedule maintenance every year in the first quarter, when demand for gasoline is low. Then, at the beginning of spring, clean air laws require refineries to begin making special gasoline blends that do not evaporate easily in warm weather. A handful of refineries that feed service stations in the Great Lakes have said they're going through the switch now, DeHaan said.
Gasoline already is the highest ever for this time of year. It's more than $4 per gallon in 10 states and Washington, D.C.
Motorists have responded by driving less and buying more efficient cars. Automakers said Tuesday that sales are soaring for smaller vehicles such as the Toyota Prius and the Chevrolet Cruze.
Overall drivers have cut back on gasoline purchases every week for more than a year, according to MasterCard Spending Pulse. MasterCard's latest survey estimated that American motorists bought 8.7 million barrels of gasoline per day last week, bringing the four-week average down almost 6 percent compared with the same time last year.
Meanwhile oil prices fell after a two-day rise. Analysts and economists say they're concerned about the effect of high fuel prices on the fragile recovery. Federal Reserve policy makers underscored those concerns, saying in meeting minutes released Tuesday that they're worried that the pace of hiring could slow if the economy doesn't pick up.
Benchmark U.S. crude fell $1.22 to end the day at $104.01 per barrel in New York, and Brent crude was down 57 cents to finish at $124.86 per barrel in London.
In other energy trading, heating oil fell by 2.21 cents to finish at $3.2275 per gallon and gasoline futures rose 1.32 cents to end at $3.3954 per gallon. Natural gas increased by 3.5 cents to finish at $2.1870 per 1,000 cubic feet.