The car shopping experts at Edmunds forecast that 1,551,643 new cars and trucks will be sold in the U.S. in May for an estimated seasonally adjusted annual rate (SAAR) of 17.0 million. This reflects a 15.9% increase in sales from April 2019, but a 2.2% decrease from May 2018.

"Dealers piled on the incentives and rolled out the barbecue grills this Memorial Day weekend to lure in shoppers and it looks like it did the trick," said Jeremy Acevedo, Edmunds' manager of industry analysis. "Good deals have been tougher to come by this year due to higher interest rates and rising prices, so it makes sense that shoppers would pounce on the chance for a steal."

Edmunds analysts note that while the May sales rebound is a positive sign for the industry, it's likely not the start of an ongoing trend.

"It's going to be an up and down year," Acevedo noted. "Automakers are still figuring out how to balance supply with declining demand, but incentive budgets aren't big enough for dealers to offer deep discounts on a consistent basis. And when those bargains go away, so do the shoppers."

Edmunds estimates that retail SAAR will come in at 13.8 million vehicles in May 2019, with fleet transactions accounting for 18.9% of total sales. An estimated 3.4 million used vehicles will be sold in May 2019, for a SAAR of 39.2 million (compared to 3.5 million — or a SAAR of 39.1 million — in April).