Gas prices in the Rogue Valley are expected to spike just in time for Memorial Day weekend, among the busiest holidays for travel of the year.

Gas prices in the Rogue Valley are expected to spike just in time for Memorial Day weekend, among the busiest holidays for travel of the year.

"I expect stations to increase prices as much as 10 to 35 cents per gallon by the conclusion of the weekend, with some stations starting to raise prices immediately," said Patrick DeHaan, GasBuddy.com senior petroleum analyst, in a news release.

By Wednesday evening, the average price for a gallon of regular gasoline in the Medford-Ashland area was $4.281, still below the record of $4.379 set on July 11, 2008, according to AAA.

But three Ashland stations at the Interstate 5 exits were posting prices of $4.49 a gallon.

DeHaan said tight supply is boosting prices significantly throughout the entire West Coast region, with the worst prices in the nation likely to soon be found in Oregon and Washington. Wholesale gasoline prices, the price stations pay before taxes and freight charges, is at its highest level ever recorded for the Pacific Northwest. While wholesale costs are rising slightly in California, Oregon and Washington will see prices rise the most over the next few days and into the weekend. While this situation is ugly for motorists, it is temporary, he said.

"I expect the situation to slowly resolve itself over the next few weeks, but as gasoline prices tend to fall slowly, motorists may not have a sense of real relief until late June or July," DeHaan said.

Marie Dodds, a spokeswoman for AAA's Northwest field office, said the GasBuddy.com figures are slightly above AAA's price estimates for the weekend, but she said motorists will feel some pain at the pump over the holiday.

"We are taking a more conservative approach when it comes to predicting the gas prices," she said. "Predicting fuel prices is like throwing darts at a board and predicting where they'll land. It's hard to say how much gas prices will go up."

Dodds said that the supply of gas to the Pacific Northwest has been restricted by a large refinery fire in the Seattle area. Dodds said gas supplies on the West Coast are at a 20-year low because of the fire and other refinery issues.

There is talk of shipping gas from the Bay Area to Oregon in the coming weeks or diverting a cargo tanker from the East Coast to bump supplies. But all this remains speculation, Dodds said.

"The stations plan to stock up on gas over Memorial Day because this is a heavy travel weekend," Dodds said. "And when there isn't as much gas to go around, then prices go up."

Dodds said there will be enough gas to go around. She doesn't expect long lines at stations and cars stranded along the highways because of lack of fuel.

"This is not like the oil embargo of the 1970s," she said. "There will be enough product for anyone who wants to put fuel in their cars."

Dodds said the price of gas in Oregon remains $4.21, which is above the national average.

"We should see that start to come down over the next few weeks," she said.

Still, that's not going to help anyone loading up the car for a trip to the lake over Memorial Day.

A survey by AAA has found that more people plan to travel this Memorial Day. This is a sign of a slowly improving economy, Dodds said.

AAA estimates that 5.6 million West Coast residents will hit the road this weekend, a 1.5 percent increase from last year.

Nationally, 35 million people will travel to celebrate the holiday, up 1.2 percent from last year's numbers.

Reach reporter Chris Conrad at 541-776-4471; or email cconrad@mailtribune.com.