The average price for regular gasoline at U.S. pumps jumped 8.5 cents in the past two weeks to a 13-month high of $3.6918 a gallon, according to Lundberg Survey Inc.
Walla Walla prices generally were running about 4 to 6 cents higher as of Sunday.
The Lundberg survey covers the period ended Friday and is based on information obtained at about 2,500 filling stations nationwide.
Prices are the highest since March 22, 2013. The average is 15.55 cents higher than a year ago, Lundberg said. Gasoline has risen 39.74 cents a gallon since bottoming out in February and is up 43 cents this year.
The highest price for gasoline in the lower 48 U.S. states among the markets surveyed was in Los Angeles, at $4.26 a gallon, Lundberg said. The lowest price was in Salt Lake City, where customers paid an average $3.29 a gallon.
The overall increase was attributed to a rise in crude oil and demand for motor fuel that over the past four weeks was up 4.6 percent from the same period a year ago, according to Energy Information Administration data.