manusapon kasosod/iStock via Getty Images

manusapon kasosod/iStock via Getty Images

California's gasoline pump prices fell $0.20 to below $6/gal for the first time since May, AAA reported on Thursday, suggesting that demand has been declining in the state.

California's seasonal gasoline stockpiles have increased to 23% above the five-year average despite refinery production lagging 8% from year-ago norms, according to Bloomberg.

Last week saw the biggest national gasoline stockpile build since January while implied demand fell to its lowest seasonal level since 1996; according to AAA, the average U.S. price for a regular-grade gallon is $4.67, down $0.12 from a week ago and $0.34 lower than a month earlier.

In the Los Angeles wholesale market, prices for the boutique gasoline required by the state fell to a discount to Nymex futures for the first time since January during the past week.

Front-month Nymex RBOB gasoline (XB1:COM) -2.3% to $3.157/gal.

ETFs: (USO), (UCO), (SCO), (USL), (DBO), (USOI), (NRGU), (NYSEARCA:UGA )

Some Wall Street firms see oil prices regaining prior highs, which would mean only temporary relief at the pump; Goldman Sachs forecasts Brent crude will hit $140/bbl this summer, while bearish Citi analysts have said Brent could sink to $65 by year-end if the economy tips into recession.