(Chicago, IL) Gas prices have shot up over the last week on both sides of the state line. AAA says the average gallon of gas in Illinois runs about $3.49, up 19-cents from this point last week, and 22-cents above the national average. Lake County saw a 17-cent increase to an average of $3.50. In Wisconsin, prices have jumped back above the 3-dollar mark for the first time in over a month, currently sitting at $3.04, a 14-cent jump from last week, but 23-cents below the national average. Kenosha County also saw a 14-cent increase to $3.06.