PORTLAND, Ore. -- Oregon’s average price for regular unleaded gas has surpassed $3 a gallon, as pump prices in the state reach their highest level since October 2008, AAA reported Tuesday -- and more price hikes are expected through Labor Day.

Oregon’s average gained four cents this week, to $3.04, while the national average rose 5 1/2 cents, to $2.78.

"The national average was at this price just before Memorial Day this year,” AAA Oregon Public Affairs Director Marie Dodds said, “Crude oil prices have been at three-month highs, which is putting upward pressure on pump prices.”

Crude oil today is trading around $80 per barrel, compared to $82 last week and $77 the week before. It’s the first time since early May crude has stayed above $80 for several trading sessions.

Investor optimism about a stronger U.S. economy, a weaker dollar and a report that showed a drop in the crude inventory in the U.S. all worked to push crude prices higher.

Whether crude can remain this high remains to be seen. Economic data continues to suggest a less-than-robust recovery.

Employment figures continue to disappoint, with the U.S. Department of Labor reporting that 130,000 jobs were lost in July, with the jobless rate continuing to hover at just under 10 percent.

And real estate industry tracking indicates that more than 20 percent of mortgage borrowers nationwide -- close to 50 percent in Bend -- are suffering from negative equity, or being “underwater,” as they owe more than their homes are worth. This trend will likely maintain the current sluggish nature of home sales as cautious buyers remain on the sidelines.

Economic conditions are not the only factor that can influence oil and gas prices. The National Weather Service has forecast an above-normal Atlantic storm season, with the atmospheric and oceanic conditions in the Atlantic Ocean and the Caribbean Sea viewed as conducive to hurricane formation.

This situation is one that bears watching as we enter the peak hurricane months between now and October. Any disruption of oil refining in the Gulf of Mexico could send crude prices higher in the short-term.

Drivers can expect higher gas prices between now and Labor Day, especially if crude maintains pricing above $80 per barrel. Gas prices normally drop significantly in September and October, after the summer driving season ends.

Check out KTVZ.COM's Pump Patrol for the latest and cheapest gas prices across Central Oregon. Do scroll down to, and zoom in on the map to find the latest citizen-reported gas prices across the region, courtesy of OregonGasPrices.com.

Five states have averages for regular unleaded at or above $3 a gallon, up from four last week, and the top five most expensive states are the same again this week.

For the 11th week in a row, Alaska is the state with the most expensive gas at $3.54, followed by Hawaii at $3.49, California at $3.18 (up a nickel), Washington at $3.12 (up four cents and fourth most expensive for the 10th consecutive week), and Oregon, which is fifth most expensive for the third week in a row. For the 10th consecutive week, South Carolina has the cheapest gas at $2.57.

Diesel prices are also on the rise. The national average gains four cents to $2.99, and Oregon’s average adds half a cent to $3.10. Hawaii is most expensive again this week at $4.00, followed by Alaska at $3.71, California at $3.27, Washington at $3.23 (up three cents and fourth most expensive, up from fifth last week), and New York at $3.19. Oregon’s average is eighth-most expensive for the 11th week in a row. A year ago, the national average for diesel was $2.66 and Oregon's was $2.68.