Last year at this time, gas prices spiked, because of a fire at an oil refinery. This year they're increasing, but not as fast or dramatic as last year.

Over the last week, gas prices increased 16 cents a gallon in Oregon to $3.49. The AAA reports the national average increased 17 cents to $3.52.

AAA's Marie Dodds says the reasons for the increase include higher crude oil prices and refineries entering their maintenance phase, so they can start producing the more expensive summer blends of fuel.

Diesel also increased over the last week, but not as much as gasoline. Diesel increased 8 cents a gallon in Oregon to $3.98.