Regular gasoline retail prices, which averaged $3.53/gal. in 2011, will average $3.56/gal. in 2012, and $3.51/gal. in 2013, according the U.S. Energy Information Administration’s (EIA) latest Short-Term Energy Outlook. EIA also lowered the average regular gasoline retail price forecast for the 2012 April-through-September summer driving season to $3.60/gal. from the $3.79 price cited in last month’s Outlook.

For the week ending June 11, the national price for regular gasoline at retail was $3.572/gal., a decrease of 4¢ from the prior week, and 14¢ below the year-ago price. Meanwhile, diesel averaged $3.781 for the same week, registering a 6½¢ drop from the week before and 17.3¢ below the year-ago price.

For the week, a gallon of regular gasoline at retail took the biggest drop on the West Coast, shedding 9.2¢/gal. to $3.972. The only region experiencing an increase for the week was the Midwest, which edged up 2¢ to $3.539/gal. Meanwhile, on-highway diesel was down in all U.S. regions, with the West Coast leading the way at an 11¢/gal. drop to $3.991. The average price of gasoline fell for the 10th consecutive week, while the average price of diesel decreased for the ninth consecutive week.

In other Short-Term Energy Outlook highlights, EIA says West Texas Intermediate (WTI) crude oil spot prices averaged more than $100/barrel over the first four months of 2012. The WTI spot price then fell from $106/barrel on May 1 to $83 on June 1, reflecting market concerns about world economic and oil demand growth.

EIA projects the price of WTI crude oil to average about $95/barrel over the second half of 2012 and the U.S. refiner acquisition cost of crude to average $100/barrel, both almost $11/barrel lower than last month’s Outlook. EIA expects crude oil prices to remain relatively flat in 2013.

This forecast rests on the assumption that U.S. real gross domestic product (GDP) grows by 2.2% this year and 2.4% next year, while world oil‐consumption‐weighted real GDP grows by 3.1% and 3.5% in 2012 and 2013, respectively, EIA says. The recent economic and financial news that points toward weaker economic outlooks could lead to lower economic growth forecasts and further downward revisions to EIA’s crude oil price forecasts.

EIA expects U.S. total crude oil production to average 6.3 million barrels/day in 2012, an increase of 0.6 million barrels/day from last year, and the highest level of production since 1998. Projected U.S domestic crude oil production increases to 6.7 million barrels/day in 2013.