It's costing more to gas up the car, and it might be a while before prices begin to move lower.

The average price of a gallon of regular in New Jersey is now $3.36. That's 17 cents more than a month ago. Gas is retailing for about $3.65 in the Philadelphia area, and $3.47 in Wilmington.

The ethanol that's part of the gasoline mixture has gone up more than a dollar a gallon in the past three weeks, said Tom Kloza, the chief oil analyst at GasBuddy.com.

"All of the ethanol that comes to the East Coast comes by train. When there's a lot of snow in the Midwest and a lot of frozen tracks and whatever the trains get delayed," he said. "So we're waiting on a lot of ethanol to come to places like Philly and Newark and New England points."

Kloza said gas could cost up to $3.50 a gallon in New Jersey by Easter as refineries switch to making spring gasoline that's more expensive to manufacture than the winter blend.

The prices should start to drop going into the summer unless a hurricane disrupts production along the Gulf Coast, he said.