For Midwest motorists, the news is particularly worth celebrating. The region saw gas spike due to problems with local refineries, prices for unleaded regular jumping to more than $4.29 in some areas, setting or nearing all-time records. In Michigan, prices have plunged back to an average $3.41, according to tracking service GasBuddy.com, and in the Southeast community of Lambertville, at least one service station is charging just $2.99 a gallon.
Prices under $3.00 have become commonplace in some regions, in fact, including South Carolina, which GasBuddy reports as having the lowest average statewide price this week, at just $3.13 for unleaded regular.
The Gulf Coast, with its close access to the oil wells of the Gulf of Mexico, as well as numerous refineries, has the lowest average price of any region, at $3.31 a gallon, according to the EIA, down from $3.38 a week ago. Alabama, Mississippi and Louisiana are among the 10 individual states with the nation's lowest fuel prices this week.
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At the other extreme? Drivers in car-crazed California can expect to pay $4.00, according to the EIA, though GasBuddy has the figure at a slightly lower $3.96. Either way, that's the highest figure for the 48 mainland states. The Energy Information Administration also reports the West Coast, in general, has the highest average price of any region, at $3.89.
Oil-rich Alaska tops the Golden State, however, at $3.99 a gallon, according to GasBuddy, which list Hawaii as the most expensive place in the country to fill up, at $4.24 for unleaded regular.
Prices can vary widely from town to town, and prices of as much as $5.09 a gallon have been reported in Los Angeles, according to GasBuddy. In South Carolina, meanwhile, the service has spotted stations selling at a low of $2.89.
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Various tracking services come up with slightly different averages, though the downward trend is clear this week. The AAA's Daily Fuel Gauge Report on Tuesday found the nationwide figure to stand at $3.48, sliding yet another penny from the beginning of the week and down nearly 14 cents in a month. But before you light the Roman Candle, the service shows that American motorists are still paying a fair bit more than a year ago, the national average for July 2, 2012, coming in at $3.33.
—By CNBC Contributor Paul Eisenstein. Follow him on Twitter