Gas prices are still rising in New Jersey ahead of the spring and summer driving season.

Robert Sinclair of AAA/Northeast says one reason for the rise — up two cents-a-gallon in New Jersey on average this week — is the switch to reformulated blends.

"The wave of switching to reformulated gasoline starts on the west coast and works its way east as we see the weather warm up," he said.

"Refineries are shutting down to perform planned and unplanned maintenance but also to tool up for the production of low vapor pressure gasoline, that summer gasoline."

That lower vapor is to help cut the evaporative emissions during the hot weather and also to prevent vapor lock.

"New Jersey's average price this week is $2.47-a-gallon, ahead of the national average of $2.42. The national average is going up fairly significantly in the last month. It's up 17 cents."

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