NEW YORK - Americans getting an early start on the Memorial Day weekend found that gasoline prices again sprinted to a record yesterday, reaching a national average above $3.83 a gallon. Some analysts predict gasoline will break past $4 as early as next week.

Twenty-four stations in the five-county Philadelphia area in Southeastern Pennsylvania already were at $4 a gallon yesterday for regular-grade gasoline, AAA Mid-Atlantic reported. No stations in the three suburban counties in South Jersey were at $4 for regular, it said.

The average price in the five Pennsylvania counties yesterday was $3.87 a gallon, up 2 cents from Wednesday and 9 cents in the last week, according to AAA Mid-Atlantic. The South Jersey counties' average yesterday was $3.70, 3 cents higher than Wednesday and 8 cents more than a week ago.

Oil prices, meanwhile, fell as a stronger dollar gave some investors reason to sell oil futures to lock in profit from crude's record run. But concerns about falling supplies and rising demand are expected to keep propelling prices higher in the days and weeks to come.

Oil's surge is contributing directly to the pain consumers feel every time they fill up. At the pump, the average national price of a gallon of regular gasoline rose 2.4 cents overnight to $3.831, according to a survey of stations by AAA and the Oil Price Information Service. Prices are 61 cents higher than a year ago.

Unlike last year, oil prices are setting record highs daily. That is pushing gasoline prices higher.

"We're going to blast past $4," said James Cordier, president of Tampa, Fla., trading firms Liberty Trading Group and OptionSellers.com.

Prices may rise as high as $3.90 on a national basis by this weekend, he said. Prices are already above $4 a gallon at many stations around the country, and are averaging more than $4 in California, New York and Illinois, among other states.

Oil prices on the New York Mercantile Exchange fell $2.36 yesterday to close at $130.81.

Analysts said oil futures were caught between the supply-and-demand concerns that boosted crude to its latest record and a desire by some investors to cash in some profit. The dollar, one of the factors that has fed oil's rally from about $65 a year ago, strengthened against the euro yesterday. When the greenback gains ground, commodities such as oil lose their value as hedges against inflation. Also, a stronger dollar makes oil more expensive to investors overseas.

The International Energy Agency, which is based in Paris, said yesterday that it was worried about whether there was enough oil to meet global demand and that it was working on a review of the world's 400 largest oil fields that could lead to a major revision in its closely watched forecasts.

"The market is really structurally tight . . . oil demand is not growing that fast, but supply is constrained," said Victor Shum, an energy analyst with Purvin & Gertz Inc. in Singapore.

Some analysts say crude has been boosted in recent days by especially strong demand for diesel in China, where power plants in some areas are running desperately short of coal after last week's earthquake. But Kevin Norrish, an analyst with Barclays Capital, said new data from China show demand for diesel was already rising quickly before the disaster. Chinese diesel imports rose 9.2 percent in April compared with last year, Norrish wrote.

Still, many analysts argue that oil prices have risen far beyond levels that can be justified by supply and demand. This school of thought believes the dollar's decline has attracted speculators to oil and other commodities, artificially inflating prices. Some analysts see signs in the price differences between the current July crude contract and contracts for delivery in future months that could mean oil prices are set to decline in coming months.