Gas prices in Michigan have gone up 18 cents per gallon as compared to a week ago, AAA-The Auto Club reported. 

Michigan drivers are now paying an average of $3.30 per gallon for regular unleaded gas. This price is 1 cent more than this time last month, but 19 cents less than this time last year. 

A 15-gallon tank fill-up would cost about $49 at those prices. 

"Despite the slight decrease in demand, Michigan motorists are seeing much higher prices at the pump," said Adrienne Woodland, spokesperson, AAA-The Auto Club Group.  

Compared to last week, Metro Detroit's average daily gas price increased. Metro Detroit's current average is $3.30 per gallon, about 12 cents more than last week's average but still 15 cents less than this same time last year. 

The most expensive gas price averages in Michigan this week were:  Traverse City ($3.34), Ann Arbor ($3.33) and Lansing ($3.32). 

The least expensive gas price averages in Michigan were: Flint ($3.23), Marquette ($3.24) and Benton Harbor ($3.29).