Gas prices below $3

ATLANTA (CNN) -- For the first time since April, the national average price of gasoline has dropped just a fraction of a cent below $3, coming in at $2.9961 per gallon in a survey out Sunday.

The Lundberg Survey, conducted by a California oil market research firm, recorded an 11 cent-per-gallon drop in the price of self-serve regular gas over the last two weeks. However, survey publisher Trilby Lundberg says not to expect any significant price drops in the near future, but rather a "modest downdrift."

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According to Lundberg, even though tight gasoline supply has been alleviated by heavier imports and increased refinery capacity, there are still 11 weeks left in the annual peak driving period when high demand will keep costs high. In addition, crude oil was priced at $69.14 a barrel at the Friday close of the New York mercantile exchange, the highest price since August 2006.

"Since then, we've just seen the nation-wide labor strike in Nigeria has been called off," Lundberg said. That will "calm nerves in oil trading pits and allow crude oil prices to retreat a little," she said.

Of major cities covered in the biweekly survey, Jackson, Miss., boasts the lowest average regular gas prices at $2.75 per gallon. Chicago was stuck with the highest at $3.39 a gallon.

Here are some prices in other cities:

--Houston: $2.87

--Atlanta: $2.92

--Baltimore: $2.92

--Boston: $2.96

--Portland, Ore. $3.00

--Las Vegas: $3.05

--Detroit: $3.09

--Denver: $3.09

--Los Angeles: $3.10

Correction: An earlier version of this story gave the wrong Jackson as the city with the lowest price for a gallon of gas. CNNMoney.com regrets the error.