Why are gas prices going up again?

BURBANK, Calif. -- Gas prices are starting to rise again. The nationwide average is $2.37 a gallon, up 34 cents in the past month.

In Southern California, the price at the pump has spiked a record 79 cents, according to AAA. Drivers are lining up to fill up before prices go up again.

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"Right now we're basically in the eye of the storm," says Allison Mac, an analyst with GasBuddy.com.

She says the problem is not the price of crude oil, which is holding steady at about $49 per barrel. The problem is at the refinery.

"In the industry we call this a first quarter climb. Every year around this time, nationally prices go up because we switch over to summer blend gas," Mac explains. "Summer fuel gasoline is actually more expensive to produce."

Refineries go through a maintenance cycle during the switch over. That means production is lower.

An explosion at the Exxon Mobil refinery in Torrance, California, last week made things worse and a strike by steelworkers at 12 refineries across the country is impacting 20 percent of oil production.

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Nationwide, gas prices had been dropping since April but have now gone up for 32 straight days.

And if you needed one more reason to hate this wicked winter, it's also costing you money. Extreme cold in the Northeast has slowed production at three refineries that account for more than two-thirds of East Coast oil output.

Analysts say prices will jump another 15 to 20 cents in the next few weeks, peaking in late March. But gas prices are still about a dollar cheaper nationwide than they were this time last year.