Slow building supply sends crude prices up, as do concerns in the Middle East.

The national average price of gas jumped seven cents per gallon over the past week due to sharply rising crude oil costs, AAA reported.

Domestic crude oil prices last week hit the highest prices so far this year as supplies built more slowly than anticipated. Nonetheless, prices at the pump—currently averaging $2.46 per gallon—remain the least expensive they’ve been since 2009 when the average was $2.06.

West Texas Intermediate crude oil prices sold at $56.71 a barrel last Thursday, and the latest EIA report showed that oil supplies increased at the slowest levels since the beginning of the year. In addition, the market is watching potential geopolitical concerns in the Middle East and a weakening dollar. Domestic oil prices are more than $10 per barrel higher than a month ago, which has contributed to higher gas prices, according to AAA.

Planned and unplanned refinery problems also continue to affect the market, and may continue to impact price heading into the summer driving season.

California, with gas prices at $3.15 continues to hold the highest gas prices. Drivers in South Carolina ($2.21), Mississippi ($2.23) and Alabama ($2.24) are paying the lowest averages at the pump.