SAN FRANCISCO --- The average price for regular unleaded self-serve gasoline here passed the $4 mark on Sunday, April 27, according to AAA's Daily Fuel Gauge Report. The precise average was $4.006, making San Francisco the first U.S. mainland city to pass the $4 mark.

Earlier this month, the island of Maui passed the $4 threshold.

"San Francisco is just the suffering pioneer," Judy Dugan, research director for Consumer Watchdog, told the Los Angeles Times. "The rest of California will soon follow, and most likely the rest of the country."

Over the weekend, the average price of self-serve regular gasoline in the Los Angeles-Long Beach area was $3.858, 5.2 cents more than last week, 24 cents higher than last month, and 54 cents above last year, the Auto Club said.

In San Diego, the price was $3.894, 6.2 cents higher than last week’s price, 26 cents above last month, and 55 cents higher than last year. On the Central Coast of California, the average price was $3.966, up 4.7 cents from last week, 22 cents above last month, and 53 cents more than last year. In the Inland Empire, the average price was $3.878, 6.5 cents over last week, up 26 cents from last month, and 54 cents higher than last year.

"For more than one-third of 2008 so far, California has been setting new daily price records for gasoline," said Auto Club spokesperson Jeffrey Spring. "Gas conservation is a top concern for motorists, so they should ensure their tires are properly inflated and that they adopt a smooth driving style to maximize their fuel economy."