(WTVO) — Gas prices have been skyrocketing this summer, driven by increased demand and reduced supply.

The average price in the U.S. hit $3.80 per gallon last week. AAA said that the biggest factor right now is not politics or supply chain issues, but is instead the heat.

Refineries are not designed to operate in temperatures above 95 degrees.

“We’ve seen a lot of refineries have trouble with the heat,” said AAA spokesperson Clay Ingram. “They’re doing a lot more maintenance, a lot more repairs, and have a lot more downtime than they typically do.”

Most of America’s refineries are located in Souther states such as Texas and Louisiana, where temperatures have soared into the triple digits for much of the past month.

Economists predict that gas prices will drop by October, but hurricane season could lead to more short-term price hikes.