A weak US dollar has sent investors to oil, pushing up crude prices over the past few months. That means higher gasoline prices this Thanksgiving.
Uncertainty about the global economic recovery means that the market is unusually unpredictable right now.
The higher prices, linked to rising oil costs, are still lower compared with last Memorial Day.
Gasoline and some heating costs are expected to be relatively low in 2009.
The weak dollar may push up energy prices by affecting supply, demand, and investor behavior.
But short-term pressures may keep them up for a while.