Updated with Ford and GM share prices and news on GM incentive plans.
Detroit (TheStreet) -- As the debate continues over whether the economy is slowing or simply being held in check by weather, February's auto sales numbers are unlikely to provide any clear indication either way.
Auto sales had been gaining steadily for four years but hit a rough patch this winter. Experts expect a sales gain of 1% or less in February. So the three-month trend shows December flat, January down 3% and February flat.
GM (GM) sales fell in December and January and are expected to fall in February. Ford (F) sales rose in December but fell in January and are expected to fall in February. Automotive News reported Thursday that next month, GM plans its second straight month of beefed-up incentives on nearly every vehicle in its lineup.
Harsh winter weather continued in many parts of the country in February and "kept a lot of people in major metropolitan areas out of dealerships for extended periods of time," said analyst Jesse Toprak of Cars.com. Partially as a result of weather and partially as a result of seasonal trends, vehicle inventories grew.
Toprak said he expects February light-vehicle sales to gain 1% from the same month a year earlier, leading to a relatively low seasonally adjusted annual rate (SAAR) of sales of 15.4 million, also up about 1% from January. Toprak thinks retail sales will rise 5%, but fleet sales will be lower, partially as a result of the weather.