gas prices

SPRINGFIELD, Ill. (WAND) - It is an ongoing cycle when the weather gets nice. When the temperature goes up, so do gas prices.

At last check, according to AAA, the national average for the price of gasoline is $2.76. States such as California, Nevada and Oregon are already at $3 a gallon. Illinois isn't that far, with an average of $2.86. Bill Fleischli, the executive vice president of the Illinois Petroleum Marketers Association, said the price of gas is driven by the market. 

"Fluctuation is by usage, by domestic and global event and taxes," Fleischli said. 

The increase in gas prices could be a change from a winter grade of gasoline to a summer grade. 

"In Illinois we have at least three grades, then there's three grades of every grade." Fleischli explained. "That's nine different grades of gasoline, just for the state of Illinois." 

Also at last check, the lowest price found in Decatur was $2.59. In Springfield, the cheapest is $2.62 and in Champaign it's $2.52. According to the U.S. Energy Information Administration, the price of gas between the months of April and September should be an average of $2.76. However, that's all speculation. 

"A tornado coming through and doing something or bad weather in the Gulf Coast, something like that could change overnight," Fleischli mentioned. 

If that's the case, the expected average is nine cents cheaper than the average of summer 2018. 

Analysts said the best way to save money is to buy gas on a Monday, before gas stations hike up the prices before the weekend travel.Â