Gasoline prices have increased for 12 of the past 14 days, reaching a national average of $2.26 per gallon despite a seasonal drop in demand. The average is 3 cents more than one week and 8 cents more than one month ago, but 6 cents less than one year ago, according to the AAA.

Hurricane Matthew caused concern about fuel availability, and affected states have experienced price jumps as a result, with an increase of 4 cents in Florida and 4 cents in South Carolina. Ports and fuel terminals in affected states were closed before the storm, but no refineries were in the path of the storm, and ports have been reopened, according to AAA.

Many states in the Midwest experienced increases due to ongoing effects of last month’s Colonial Pipeline leak and seasonal refinery work. Five Midwestern states were on the list of top 10 weekly increases, including Indiana (11 cents), Michigan (10 cents), Missouri (8 cents), Ohio (8 cents), and Illinois (6 cents).

West Coast prices remained steady. All six states with an average of $2.50 or more were in that region, including Hawaii ($2.84), California ($2.79), Washington ($2.72), Alaska ($2.64), Oregon ($2.52), and Nevada ($2.50).

The national average price for diesel climbed to $2.445, an increase of almost 6 cents from last week’s price of $2.389, according to the U.S. Department of Energy.