As summer heads into its last month, the price of a gallon of gasoline keeps rising.
In some states, a return to $4 a gallon is becoming a possibility.
"It's a very volatile market. Anything can set it off," said David Cawton, a sales and service specialist for AAA. "We saw that it was going down in the beginning of July and August, but it's really shot up."
Cawton said AAA forecasted prices to go down, but that hasn't been the case.
"There are two main factors contributing to it right now," he said. "We've got two major refineries closed down right now, one in California and then we've got one up north as well."
Cawton is referring to a refinery fire this week in California and a pipeline leak in the Upper Midwest that have hit at just the wrong time.
He also said Tropical Storm Ernesto is an issue, with the storm going over Mexico's oil production, a contributing factor to rising prices.
In the last week, the national average price at the pump is up 13 cents to $3.65 a gallon. That's 27 cents a gallon higher than it was a month ago.
By Friday, the price could be higher than it was a year ago. Last year, the cost of gasoline fell by 40 cents a gallon between Labor Day and Christmas.