US Drivers Get Christmas Surprise With Lowest Gas Prices Since 2008 The national average gas price hovers around $2 a gallon for regular.

 -- Drivers continue to get reverse sticker shock, often spending $20 or less at the pump. Christmas Day gas prices are at their lowest levels since 2008, with many U.S. drivers paying around $2 a gallon for regular-grade, and prices may inch lower in the coming weeks.

"Just like every year, it depends on where you are to see if your stocking is stuffed or the Grinch is alive," GasBuddy senior petroleum analyst Patrick DeHaan told ABC News today.

In California, prices are mostly higher than they were a year ago, where prices range from around $2.60 to $3 in some cities, thanks to factors like taxes and fees. But the national average is around $2.02 a gallon for regular, according to the Energy Department's weekly estimate this past Monday, down 1 cent from last week and about 37 cents from a year ago.

Back in 2008, the average price for a gallon of regular was around $1.63, according to the U.S. Energy Department.

Energy Department's Energy Information Administration Weekly Prices for Regular:

Dec. 22, 2008: $1.635

Dec. 21, 2009: $2.546

Dec. 20, 2010: $2.934

Dec. 19, 2011: $3.183

Dec. 24, 2012: $3.205

Dec. 23, 2013: $3.198

Dec. 22, 2014: $2.341

DeHaan said the cause of the lower gas prices these days is "good old-fashioned supply and demand."

With temperatures around 60 to 70 degrees along the East Coast, fewer people are using heating oil.

"The fact that it’s been a very warm winter is leading to much less heavy fuel demand and leading to high inventory," he said.

In addition, oil inventories are about 30 percent higher than they were about a year ago.

"We’re awash not only in crude oil but diesel and heating oil, compared to last year, “DeHaan said.

He said he expects prices to continue declining in January and early-February.

"But like all good things, the party is probably is going to end sometime in mid- to late-February when prices tend to go higher,” DeHaan said, “after the sweetness of Valentine’s day chocolates is gone.”