Diesel fuel prices, which averaged $3.94 per gallon last summer, are projected to average $4.21 per gallon this summer, according to the Energy Information Administration's Short-Term Outlook.
Monthly prices will peak at $4.25 per gallon in the middle of the driving season, the EIA predicts.

Regular gasoline retail prices are forecast to average about $3.95 per gallon, peaking in May at a monthly average price of $4.01 per gallon. EIA expects regular gasoline retail prices to average $3.81 per gallon in 2012 and $3.73 per gallon in 2013, compared with $3.53 per gallon in 2011.

EIA has lowered the forecast 2012 average U.S. refiner acquisition cost of crude oil by $2 per barrel from last month's Outlook to $112 per barrel, still $10 per barrel higher than last year's average price. EIA expects the price of West Texas Intermediate (WTI) crude oil to average about $106 per barrel in 2012, the same as in last month's Outlook but $11 per barrel higher than the average price last year. Constraints in transporting crude oil from the U.S. midcontinent region contribute to the expected discount for WTI relative to other world crude oil prices.

EIA expects WTI prices to remain relatively flat in 2013, averaging about $106 per barrel, while the average U.S. refiner acquisition cost of crude oil averages $110 per barrel.

The warmer-than-normal weather this past winter also contributed to high natural gas working inventories that continue to set new record seasonal highs, with March 2012 ending at an estimated 2.48 trillion cubic feet (Tcf), about 57% above the same time last year. EIA's average 2012 Henry Hub natural gas spot price forecast is $2.51 per million British thermal units (MMBtu), a decline of $1.49 per MMBtu from the 2011 average spot price. EIA expects that Henry Hub spot prices will average $3.40 per MMBtu in 2013.

Daily and weekly national average prices can differ significantly from monthly and seasonal averages, and there are also significant differences across regions, with monthly average prices in some areas exceeding the national average price by 25 cents per gallon or more.