The U.S. Department of Energy has raised its oil and diesel price forecasts. The DOE's Energy Information Administration expects the price of West Texas Intermediate crude oil to average about $83 per barrel this winter,

according to its monthly Short-Term Energy Outlook, released Tuesday. That's a $5.50-per-barrel increase over last winter and $3 per barrel more than in last month's Outlook.

The agency, noting that growth in global oil consumption remains strong, predicts crude prices will rise gradually to $87 per barrel by the fourth quarter of 2011 as U.S. and global economic conditions improve. EIA's forecast assumes U.S. gross domestic product (GDP) grows by 2.6 percent in 2010 and 2.2 percent in 2011, while world real GDP weighted by oil consumption grows by 3.9 percent and 3.3 percent, respectively.

Retail diesel fuel prices are expected to average $3.09 per gallon this winter, an increase of 29 cents per gallon over last winter.

In 2011, higher crude oil prices combined with strengthening refiner margins push annual average prices for diesel fuel to $3.19 per gallon. That's up from last month's forecast of $3.14 for next year.

EIA expects regular-grade motor gasoline retail prices to average $2.84 per gallon this winter, 19 cents per gallon higher than last winter.

More details on the Short-Term Energy Outlook are available on the EIA website.