"All grades combined, gasoline now costs $1.83, up about 2½ cents in the past two weeks," Trilby Lundberg of the Lundberg survey told CBS Radio News. Her firm regularly polls 8,000 stations across the United States. "Self-serve regular now costs $1.80 nationwide, also up about 2½ cents."
Gasoline prices are up 31.5 cents per gallon nationwide since late December, Lundberg said.
"The prices keep breaking their own records every week," she said.
The national weighted average price of gasoline, including taxes, at self-serve pumps Friday was about $1.79 for regular, $1.89 for midgrade and $1.98 for premium.
"Self-serve regular is lowest in Tulsa, on average at $1.59, and the highest in San Diego, at $2.22," Lundberg said. That's up 10 cents from two weeks ago.
"The reasons are the same," she said: "Very strong crude oil prices, strong gasoline demand in the U.S., and stress on the refining system because of tight capacity and our many environmental protection formulas for gasoline."
The effect on gas prices has been magnified this year because commercial gasoline inventories are already low. The federal government said last week that gasoline prices will rise another nickel a gallon nationwide before the end of June but return to current levels before the fall.
"It isn't possible to know if prices are soon peaking and may drift downward, or whether we have a ways to go," Lundberg said, "but if crude oil prices stay above $37 a barrel, as they are right now, then price hikes at the pump are a possibility."
The hardest hit areas will likely be the West Coast and the Northeast.