Hawai'i's gasoline prices will likely drop for a fourth consecutive week on Monday as motorists benefit from falling wholesale prices along the Gulf Coast.

Drivers could see a decline of about 10 cents a gallon if wholesale market trends continue today, according to Advertiser calculations. That would bring the total decline over the past four weeks to 84 cents.

"In four weeks they've come down dramatically," said Frank Young, a former Chevron station owner and a proponent of the gas cap. "Would they have come down without the gas cap, is the million-dollar question. Historical behavior shows they rarely ever came down."

Chris Sagaysay is just happy gas is getting cheaper.

"Anytime it drops, it's good news," said the 22-year-old who commutes from his home in Waialua to a job in Kalihi.

Sagaysay said he signed up for a Costco Wholesale membership recently just to take advantage of the warehouse club's often market-leading gasoline prices.

Costco in Iwilei sold regular for $2.69 a gallon yesterday as did a Chevron station on the corner of Houghtailing and North School streets. Other stations that were still selling regular in the high $2.80 range are likely to cut pump prices later this week.

Hawai'i's wholesale gas cap law, the only one in the nation, was intended to bring the state's price movements into sync with those nationally. Prices soared immediately after the cap took effect on Sept. 1 in response to supply disruptions caused by hurricanes Katrina and Rita in the Gulf Coast.

This week prices are finally dropping to below where they were before the cap took effect. The average regular price on O'ahu was $2.84 on Aug. 31.

Prices could fall below $2.60 a gallon next week on O'ahu if the state confirms a 10-cent cut in the cap when it announces the new ceiling tomorrow. The new cap takes effect Monday.

"I think it's a good thing," said Chris Sanchez, 29, of Makiki. "At first it seemed inflated but now we see the leveling off."

The cap is based on prices in New York, the Gulf Coast and Los Angeles and are adjusted weekly.

Oil closed below $60 a barrel yesterday for the first time in three months.

At $2.48 a gallon, the nationwide average yesterday was below $2.50 for the first time since mid-August and down 55 cents a gallon from its peak of $3.03 following Hurricane Katrina, according to the Energy Information Administration.

The dip could just be a seasonal occurrence. The period between Columbus Day and Thanksgiving traditionally sees a lull in fuel prices, said Tom Kloza, chief oil analyst at the Oil Price Information Service in Wall, N.J.

Kloza predicted the nationwide average price will bottom out between $2.10 and $2.35 a gallon, and is sticking to a prediction he made last week that gas could fall below $2 a gallon in some states.

But don't get used to it. Prices will go back up, Kloza said.

"Wherever we bottom out in the next six weeks, you can just take that number and add 50 or 75 cents, and that's where we're going in the spring," he says.

The cheapest statewide average: Oklahoma's $2.14, according to travel club AAA. Hawai'i had the highest prices, averaging $3.01 a gallon. Hawai'i's average was 24.5 percent higher than a year earlier, while the national average was 22.7 percent higher.

Hawai'i's price cap only regulates wholesale prices and allows gas stations to set whatever price they want. The retail price drops don't automatically occur with cap cuts because some stations need time to sell remaining higher-priced inventory before they take delivery of cheaper product.

Honolulu's gasoline prices are down from a high of about $3.59 a gallon reached on Sept. 17 as reported by the AAA's Daily Fuel Gauge report.

Young, the gas cap proponent, said Hawai'i's price volatility, while rising from pre-cap times, is now in line with about half of U.S. states. The gap between O'ahu and Neighbor Island prices is also narrower, he said.

Reach Greg Wiles at gwiles@honoluluadvertiser.com.