Pennsylvania gas prices have fallen 6.4 cents per gallon in the past week, averaging $2.86 per gallon on Wednesday, according to gasbuddy.com's daily survey of 5,269 stations.

The average price for gasoline in the Northumberland, Montour, Snyder and Union counties was the same as the state, according to AAA. But gas prices varied, depending on where drivers bought their gas. They were paying an average of $2.99 a gallon in Elysburg, but as low as $2.70 a gallon in Lewisburg. Sunbury's average price was $2.89.

"Sunbury is one of the more expensive in the Susquehanna Valley," said AAA spokesman Jim Garrity, noting this area's proximity to supply is not as close as some other parts of the state.

The closest refineries are in Philadelphia, he said.

"You're more expensive than the state," said Garrity. "The upper counties (Northern Tier) are more expensive."

Patrick DeHaan, head of petroleum analysis for GasBuddy, said gas costs more in Sunbury probably because of lower demand.

"I think Sunbury doesn't have a whole lot of competition," said DeHaan, who is based in Chicago. "It doesn't have a price leader to bring prices down."

Because the stations don't sell as much gas, it takes them longer to sell the gas they bought at a higher price.

"The behavior we see is gas stations want to get rid of that inventory before they drop the price," DeHaan said.

He said Lewisburg stations sell gas for less, likely because of a combination of more competition in a higher traffic area and a price leader bringing prices down to lure more customers.

Both DeHaan and Garrity said they expect prices to continue to go down, barring any major disaster that would affect refineries' production.

GasBuddy reported gas prices in Pennsylvania are 15.3 cents per gallon lower than a month ago and 19.2 cents per gallon lower than a year ago.

"The fall has come amidst a deep drop in oil prices set in to play on worries that tariffs could slow economic growth, reducing oil demand," DeHaan wrote in a news release. "The decline at the pump is likely to continue but may slow down in a few couple weeks as President Trump made a deal with Mexico over the weekend to avoid tariffs. With gasoline inventories also growing in most areas of the country, the transition to summer gasoline complete, motorists will continue to see prices moving lower as the summer driving season gets underway."

Garrity also noted nationwide crude oil prices are low and supplies are building up.

"Gas price declines this week were supported by a sizeable build in gasoline stocks – nearly 1.9 million barrels, bumping total inventories to 65.1 million barrels," he stated.

"Barring any sort of outlying anything related to crude oil," Garrity said, citing a major hurricane or turmoil in the Middle East, "We may have gotten all the major increases out of the way. That is not to say gas prices are going to be plummeting in the weeks ahead."

He said motorists should be "cautiously optimistic." He said there could be some small increases when there is increased demand, such as around the Fourth of July.