As of Tuesday, AAA reported gas prices in Minnesota had jumped 19 cents per gallon over the past seven days -- 18 cents higher than the national average. Experts say the culprit is Chicago. The Pioneer Press reports the metropolis is fueled by a number of Midwest refineries, but three of those refineries have been completely or partially off-line for maintenance.

Gas prices have come down an average of 18 cents from a week ago, and about 33 cents from one month ago, according to twincitiesgasprices.com. The cheapest gas is in Bloomington (more than a dozen stations had gas in the $3.23-3.29 range.) The three most expensive stations were in South St. Paul ($3.99), North St. Paul ($3.98) and Minneapolis ($3.74).

The average price for a gallon fell 13.6 cents to $3.49 over the weekend. It's good news, of course, but experts warn that the market is still very sensitive to global politics.

Even though crude oil prices are going up, the cost of gas is headed south for the winter. Prices at the pump are down seven cents in a week and the forecast is they'll keep dropping with the temperatures.

Prices for a gallon of gasoline in the Bemidji area are among some of the highest in the country according to AAA. Spokeswoman Gail Weinholzer tells Minnesota Public Radio that Hurricane Isaac as well as a pipeline problem in Wisconsin and refinery problems in Chicago have bumped prices up at the pump. Minnesota's average is $3.95, which is eight cents higher than the national average.

Gas prices are going down and in fact are lower now than they were last year. One expert says refineries are wrapping up maintenance and getting back to production.