(Reuters) - The pace of U.S. auto sales is expected to rise 3.3% in September from the prior month, helped by strong consumer demand and the Labor Day holiday, industry consultants J.D. Power and LMC Automotive said on Friday. The seasonally adjusted annual sales pace for September is expected to be 15.7 million vehicles, up from 15.2 million vehicles in August, but down from 17.3 million units a year earlier, the consultants said. Advertisement U.S. auto sales have bounced back since hitting a pandemic-fueled bottom in April, leading major automakers to ramp up production and boost weak inventories at dealerships. However, rising COVID-19 cases in the U.S. states have increased the uncertainty over a speedy economic recovery. Advertisement “Lockdown measures are now fairly loose in many parts of the world, but a risk of the reintroduction of more restrictive and widespread measures certainly cannot be ruled out,” said Jeff Schuster, president of the Americas operations and global vehicle forecasts at LMC Automotive. Total sales in September are projected to reach about 1.29 million units, compared with about 1.33 million units in August, and about 1.28 million units a year earlier, the consultants said.