Motorists will pay more to fill their gas tanks this year as prices rise to their highest level since 2014, according to multiple forecasters and the federal government.

GasBuddy predicts a 19-cent a gallon average rise nationwide this year over 2017 to $2.57 a gallon, the highest since 2014.

Average prices are already topping $2.50 in 11 Northeast and mid-Atlantic states, including $2.51 in Maine and $2.53 in both Vermont and Massachusetts, according to AAA.

GasBuddy, which monitors gas prices, released its 2018 Fuel Price Outlook on Jan. 2. Prices will peak at $2.73 a gallon in May, GasBuddy predicts.

“OPEC bears much of the responsibility for cutting oil production, leading oil inventories to begin 2018 nearly 50 million barrels lower than a year ago. Yet, understanding many factors, including OPEC, fuel taxes, the economy and their impact on supply and demand is integral to providing a thorough and balanced outlook on gas prices for 2018,” Patrick DeHaan, head of petroleum analysis at online gas-price estimator GasBuddy, said in a prepared statement.

DeHaan suggested motorists outsmart the pump by shopping around for the lowest prices and driving in a way that conserves fuel.

AAA said 2018 started with the highest national gas price average — at $2.49 a gallon — since 2014, when gas prices were more than $3 a gallon. High traffic over the recent holidays drove up gas prices, and in the new year motorists, including in the Northeast, are seeing pump prices as much as 13 cents a gallon higher than one week ago.

AAA’s figures, also released Jan. 2, did not predict the entire year. The automobile association did say higher holiday prices will ease.

“Now that the holiday season is in the rearview mirror, motorists can expect gas prices to trend cheaper this month as we are likely to see a significant drop in gasoline demand,” AAA spokesperson Jeanette Casselano said.

The U.S. Energy Information Administration’s nationwide estimate this year is $2.51 a gallon, up from $2.43 in 2017.

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