Gas prices jumped 20 cents in two days at most stations in Bismarck, and experts say there's probably no relief in sight.

Prices for regular unleaded gasoline rose from $2.29 a gallon at most stations in the area on Tuesday, to $2.49 a gallon by Thursday afternoon.

The state average on the same day was inline with the nation's average at $2.41 a gallon, according to AAA fuel gauge reports.

For the state, that's 35 cents higher than Feb. 1, according to AAA reports.

Mike Rud, president of the North Dakota Petroleum Marketers Association, said prices are driven higher in spring due to the heavier driving season.

And winter storms on the East Coast means more fuel consumption, another factor in higher prices, Rud said.

"It's just getting to that time of the year again where demand's increased," Rud said.

Wednesday, the U.S. government released a report that stockpiles of gasoline dropped an unexpected 1.9 million barrels, bringing gasoline inventories 5.7 million barrels lower than they were this time last year.

Prices a barrel closed at a two-month high of $62.11 on Thursday, reacting to news of the product shortage.

"I don't expect to see the end of it yet,"said Gene LaDoucer, with North Dakota AAA. "Over the next four to six weeks, I would expect gasoline prices would continue to rise."

LaDoucer added that refineries are switching from winter blends to summer blends, which means reducing inventory and cutting into supply.

Consumers must watch how much fuel they're using, LaDoucer said, because prices may continue to be volatile in the near future.

To track national and state gas prices, check out www.fuelguagereport.com

(Reach reporter Crystal R. Reid at 250-8261 or at crystal.reid@;bismarcktribune. com.)