Regular gasoline averaged $4.56 a gallon in the Marquette area on Wednesday, Oct. 28, about 34 cents higher than a week earlier, according to AAA.

The local average fell about 4 cents from Tuesday but remained above last week’s $4.23. Michigan’s statewide average was $4.71, compared with $4.25 nationally.

Refinery disruption affected regional prices

An unexpected shutdown of a key unit at ExxonMobil’s Joliet refinery in Illinois contributed to rising gasoline prices across the Great Lakes region, Bloomberg reported Oct. 22.

Bloomberg reported increases in Michigan and Ohio, with effects also spreading to Wisconsin, Indiana and Illinois.

A separate CNN report published by Scripps News described the outage as another strain on fuel supplies. It reported that a return to normal refinery operations could ease pump prices, while higher oil costs could limit that relief.

Prices remain above last year

AAA’s Marquette-area average was about $1.64 higher than a year earlier, when regular gasoline averaged $2.92.

The figures are area averages, rather than prices available at every station. AAA updates its state and metropolitan price comparisons daily.