The national average pump price for a gallon of regular gasoline is a penny higher Wednesday than it was on Monday. At $2.90, the average is 20 cents a gallon more than it was just one month ago.

24/7 Wall St. reported that the state hardest hit by rising gas prices is California, where the average price was $4.08 a gallon Wednesday morning, down a penny from Monday’s average price. The state’s drivers pay $0.7368 per gallon in federal and state taxes, the second-highest rate among the lower 48 states. Only Pennsylvania drivers pay more, $0.771 per gallon, according to the American Petroleum Institute (API).

While drivers in no other state are paying $4 or more for a gallon of gas, drivers in nine more states are paying an average of more than $3 a gallon, according to Wednesday morning data collected by GasBuddy. They are Hawaii ($3.74), Nevada ($3.51), Washington ($3.49), Oregon ($3.38), Alaska ($3.36), Arizona ($3.15), Utah ($3.07), Pennsylvania ($3.05) and Idaho ($3.03). Gas prices are well on their way to a 12-month high.

While pump price increases have moderated, they will continue to rise for the next several weeks, as the Memorial Day holiday weekend approaches and demand for gasoline rises during the summer driving season.

For the full story click here.