LANSING, Mich. (WLNS) — Michigan’s trend of lowering gas prices may have come to a halt, with a rise of 11.2 cents per gallon since last week in average gas prices in Lansing and a rise of 13.9 cents per gallon since last week in Flint.

According to GasBuddy, the cheapest station in Lansing Sunday was at $3.39 per gallon of regular unleaded, and the most expensive in the city was at $3.99 per gallon. Statewide, the lowest price in the state Sunday was $3.29 per gallon, while the highest was $4.40 per gallon.

Rises in gas prices were more moderate in Ann Arbor (up by 1.7 cents since last week) and Grand Rapids (up by 6.7 cents).

“The national average rose slightly over the last week due to continued refinery challenges in the western U.S. that have pulled gas prices up considerably in some states, while some 1 in 5 states have seen average gasoline prices decline in the last week,” said Patrick De Haan, head of petroleum analysis at GasBuddy. “With the transition back to cheaper winter gasoline now upon us in nearly every state, we should see prices eventually cooling back off, but if refinery issues continue to develop or linger, especially now that we’re entering maintenance season with less availably capacity online, the expected decline could certainly be offset.”

De Haan added that oil prices are now $91 per barrel for the first time in nearly a year and that trends are continuing that way due to extended cuts in oil output by Saudia Arabia and Russia.