Thanksgiving is reportedly the third most dangerous holiday for deaths in the United States. Between 1998 and 2008, there was an average of 572 deaths annually on U.S. highways during the Thanksgiving holiday, making it the most deadly four-day holiday period on American roads. The 4th of July is the deadliest three-day holiday weekend.
The National Safety Commission blames speeding and tired and/or sleepy drivers for the high number of deaths around Thanksgiving.