The month-long slide in gasoline prices likely will continue in the coming weeks, providing more relief for shell-shocked motorists heading into peak driving season.

USA Today reported that nationally, gasoline averages were $3.80 a gallon — about 12 cents below this year’s peak and nearly 20 cents below 2011’s $3.99 a gallon. Gasoline prices have now fallen 18 straight days and 25 of the past 28.

“We can expect the U.S. retail average to flirt with $3.75 a gallon shortly and expect to pay 10 to 25 cents a gallon less in the next couple months,” says Tom Kloza, chief analyst for the Oil Price Information Service.

Crude oil prices fell sharply in early Friday (May 4) trading after the Labor Department reported weaker than expected job gains last month. That roiled Wall Street and the commodities market. Benchmark West Texas crude oil sank 4% to $98.52 a barrel, its biggest one-day drop of 2012 and the first time crude had fallen below $100 since February.

Weaker-than-expected economic news in the U.S. and Europe has helped push prices lower for several weeks. So have supply problems at U.S. refineries and easing tensions in the Middle East, where a possible showdown with Iran had driven speculators to push crude oil prices up sharply since the start of the year, spurring some forecasters to predict gasoline would surge well above the record $4.11 a gallon average set in July 2008.

But with consumption down, sustained global economic weakness and rising production up — the Energy Department said earlier this week that U.S. production was at its highest levels since 1999 — this year’s price run-up ran out of steam six weeks before the peak of summer driving season.

Lowest prices: the Midwest, where gas could fall below $3.50 a gallon. Highest: the West coast, where prices could remain closer to $4 as supplies are tight .