Concerns about illness or inflation aren’t stopping Americans from hitting the roads and airports this holiday season. But a massive winter storm might. Forecasters are predicting heavy snow, ice and powerful winds between Thursday and Saturday across much of the country. Delta, United and other airlines say they are loosening their change fee policies so travelers can choose new flights and avoid the bad weather. The weather added uncertainty to what’s expected to be a busy travel season. AAA estimates that nearly 113 million people will travel at least 50 miles from home between Dec. 23 and Jan. 2. That’s 4% higher than last year.