SPRINGFIELD, Mo. -- From Monday to Tuesday, gas prices increased an average of eight cents per gallon around Missouri and an average of seven cents in Arkansas, according to Gasbuddy.com.  Economists said the prices are up in anticipation of Hurricane Isaac, as well as increased demand for Labor Day travel.

"Knowing that it's going to be more expensive we'll probably not take unnecessary trips, carpool more often, and try to consolidate our trips together," said Mandy Cazzel of Springfield. 

David Mitchell, director of the Buereau of Economic Research at Missouri State University, said the storm could damage oil refineries on the coast, and that would likely have a ripple effect.

"Now, all of a sudden, gas being refined in that area that is going to go to these different markets is going to be in short supply," Mitchell said.

So far, in anticipation of the storm, prices have shot up an average of 3 cents nationwide. The climb started Friday; that's when meteorologists were able to predict the brunt of the storm would likely miss Florida and slam into the Gulf Coast.

The hurricane is set to hit at a time when gas is already in high demand for Labor Day travel.
AAA estimates a close to three percent increase in travel this year compared to last year.

"We'll fill up before we go and fill up before we come back," said Jolene Elliott of Sparta.

Elliott and her family are heading to visit family for the holiday.  She said the trip will likely cost the more than $120.  The anticipated increases could hit her family and thousands of others like them hard.

"My husband drives a big SUV too.  We've talked about carpooling before," Elliott said.

Mitchell said the Labor Day price increases could linger up to two weeks.  If the hurricane damage is severe, increases could last a lot longer.

"If it really gains a lot of strength over the next day or two, and it really slams the coast hard and shuts things down, we're gonna see increases of a whole lot more than just a penny or two," Mitchell said.

Economists said the increases already seen stem from concern about what could happen in the next couple days.  Mitchell said it is tough to know just how high prices could go, but he estimates a five to ten cent increase if some of the refineries are damaged.