While gasoline prices are under $4 in Kansas, they have continued to increase as the busy driving season approaches.

The average price of gasoline is now over $4 per gallon in four states and Washington, D.C., as a three-month surge in pump prices continues.

The nation’s capital, Illinois, California, Alaska and Hawaii all had average gas prices above $4 on Wednesday, according to AAA, Wright Express and Oil Price Information Service.

The average price in Salina, as of Friday morning, jumped to $3.69. The lowest price in Kansas was reported in Junction City at $3.49, while the highest price was reported in Hays at $3.99.

Nationwide, gasoline has soared by nearly 54 cents this year to an average of $3.81 per gallon.

Prices are rising as service stations pass along the higher cost of crude. Benchmark oil prices have risen by nearly 8 percent since January. Oil accounts for about three-quarters of the cost of a gallon of regular gasoline, according to the government.

Pump prices also tend to jump this time of year as gasoline suppliers sell off their remaining stocks of winter gasoline to make room for a different grade of gasoline required in the summer. The seasonal switch causes a temporary supply dip that pushes prices even higher.

On Wednesday the government indicated that the switch was under way. Gasoline supplies fell by 1.4 million barrels last week, according to the Energy Information Administration’s weekly report.