Gas prices on Long Island reached another record Friday with drivers paying an average of $3.55 for a regular gallon at the pump.

Crude oil prices soared above $115 a barrel and inventories dropped, just weeks before the start of the summer driving season. AAA says gas prices on the Island increased an average of more than 20 cents in less than a week.

The change caught many gas stations off guard.

"We don't have enough fours to post the right price," says Curt Reichert, an Exxon Station owner. "We're getting fives just in case."

According to the federal energy department, the higher costs are caused by the weakening value of the dollar against other currencies. That dollar, in turn, buys less crude oil.

AAA says the cost of gas could rise even higher throughout the summer.

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GasBuddy.comGasPriceWatch.comFuelEconomy.govAAA Fuel Guage ReportEnergy Information Administration