Pinch at the pump grows tighter

Summer is still weeks away, but drivers may feel as if it's already here when they fill up at the pump.

Gas prices have risen 8 cents a gallon in the past week in much of California. With a trend of prices on the rise, the Web site modestogasprices.com listed an average of $3.82 for regular gas Monday.

That suggests that the previously unthinkable price of $4 a gallon is almost certain this summer, when prices typically rise because of increased driving.

That mark has been surpassed by other fuels. Diesel is about $4.32 a gallon, and midgrade and premium gasoline prices average at or slightly above $4 a gallon, according to the same site. Experts cite a number of possible causes for the spike, including a record price for a barrel of oil and refineries changing to a more expensive blend of summer gas. On April 8, the federal Energy Information Administration predicted that prices on the West Coast for a gallon of regular gas would average $3.90 in May and $3.88 in June.

California prices are typically higher because of a special gas blend used in the state and the difficulty of shipping gas in from other parts of the country.