A USA Today analysis shows that since Dec. 1, police have reported at least 42 pileups with at least 10 vehicles, or at least five vehicles when someone was killed. That's a rate of almost one a day. One of the most recent occurred on Jan. 23, a 46-vehicle crash near Michigan City, Ind., that killed three, injured more than 20 and left some lanes of interstate 94 still closed into the next day. For all of 2013, at least 107 pileups occurred on U.S. roads or about two a week.
Experts point out a common ingredient: people driving too fast for conditions.
USA Today's analysis found that icy roads were a factor in 15 pileups last year and snow or freezing rain in an additional nine. In all, wintry weather accounted for about 40 percent of pileups.