Gas prices across the U.S. have hit record highs for the past 11 days straight, according to data from the American Automobile Association (AAA) reaching $4.59 a gallon (3.785 liters) on average on Friday. That’s a slight increase over Thursday’s previous record high that was 16 cents more than the week before, around 50 cents more than a month ago and a whopping $1.55 over the previous year.

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What’s perhaps more alarming is that the records come at a time of year when gas prices are normally low. “Typically this time of year we are in a little bit of a lull,” Andrew Gross, a national spokesman for AAA, told Fox Business. “There is often a demand lull between spring break and Memorial Day and we had a little bit of it about two weeks ago, but then last week,… there was actually an increase, which is very unusual. I don’t think I’ve ever seen that.”

Source: gasprices.aaa.com

According to AAA data, the price of gas was $4.593 per gallon  in all 50 states on Friday. In California, though, which had the highest average retail gas price in the country, drivers were paying $6.064 per gallon.

The reasons for the high prices are many but some of it has to do with high demand, Gross said. Tighter supply is also playing a role, though. If Russia’s invasion of Ukraine continues, he thinks drivers should expect high prices for months to come. That, among other factors, is leading to volatility in the oil market, which is pushing the price of a barrel of oil extremely high.

Source: gasprices.aaa.com

“Back in August, a barrel of oil was about $64 so we’re $40 plus more and that’s putting a lot of upward pressure because oil accounts for about 60% of the cost of what you pay at the pump, so the more expensive the oil, the more expensive the gasoline,” Gross said.

In addition, AAA writes that gas stations are now switching over to their summer blends, which normally adds seven to 10 cents per gallon to the price of gas. The event happens every year, so it’s no surprise, but we are currently in the midst of it and it won’t finish until June. All of which means that it’s likely to be a very expensive summer for drivers.