Gas prices in Maryland reached a six-month high of $3.54 per gallon on Friday, a price last seen at local pumps in September, according to AAA.

Increases in gas prices are common at the start of spring.

Friday's statewide average price of gas is 7 cents more than a week ago and 12 cents more than a month ago, but 14 cents lower than this time last year, the driver advocacy organization found.

The spike is consistent with "an annual springtime ritual: the often shocking increase in pump prices as the weather turns warmer," said Christine Delise, a AAA spokeswoman, in a statement.

"This time of year refineries across the USA are undergoing maintenance ahead of the EPA-mandated switchover to the production of more expensive summer-blended gasoline," AAA said Friday. "The process, which is slated for completion by April 1 in most years, is often accompanied by painful increases in retail gasoline prices for the world's largest energy consumers, and this year is no exception."

High crude oil prices have also played a role.

The national average price for gas also reached a six-month high Friday of $3.53 per gallon — which is 2 cents higher than last week and 15 cents more than a month ago, but 16 cents lower than this time last year.

krector@baltsun.com

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