Gas prices jump 18 cents
Prices are now up more than 60 cents since late January due to refinery outages.
(CNN) -- Gas prices jumped more than 18 cents over the past two weeks to a national average of $2.79 a gallon of self-serve regular, a national survey said Sunday.
That marks a rise of 60 cents since late January, said Trilby Lundberg, publisher of the "Lundberg Survey," which tallies prices every two to three weeks at about 5,000 gas stations.
The current price is about 12 cents higher than it was a year ago, but still 24 cents lower than the record high set last August, she said. The latest surveys were carried out April 6 and March 23.
Lundberg attributed the price increases to problems at several refineries that cut gasoline production at a time of rising demand. For example, Valero Energy Corp. (Charts), the nation's largest independent refiner, shut its refinery in McKee, Texas, after a fire on Feb. 16. Though company officials are predicting a partial return to production within days, a full resumption is not expected until late in the year, she said. (See correction).
And the hemisphere's second-largest refinery - the Hovensa Refinery on the Island of St. Croix, the Virgin Islands - has shut for 10 days of maintenance, she said.
Lundberg said OPEC's million-barrel-a-day cut in production is also helping keep crude prices strong.
The cuts came as demand for gasoline was high, driven by a strong economy and the extra hour of daylight provided by this year's early arrival of Daylight Saving Time, she said.
Iran's release of 15 British sailors and marines resulted in a dip in prices, but "had no huge effect," Lundberg said.
Drivers in Charleston, S.C., paid the least, at $2.54 a gallon of self-serve regular; drivers in San Francisco paid the most, at $3.30.
Here are some other prices from around the country:
Salt Lake City: $2.58
Pittsburgh, Pa.: $2.71
Portland, Ore.: $2.95
Saint Louis: $2.69
(Correction: An earlier version of this story incorrectly stated that Valero's McKee, Texas, refinery was the nation's largest. CNNMoney regrets the error. Return to story).