When is a driver most likely to fall asleep at the wheel?

Drowsy driving crashes peak between midnight and 6 AM, when the body's circadian rhythm pushes hardest toward sleep, with a secondary peak in the mid-afternoon (roughly 1 to 4 PM). The body is biologically programmed to sleep at night and slow down in mid-afternoon, and this drive does not disappear just because you are at work. Drivers on overnight schedules are at elevated risk regardless of how much sleep they had during the day, because daytime sleep is generally less restorative than night sleep. The mid-afternoon dip is real but milder. Plan trips to avoid driving during your normal sleep hours when possible. If you must drive overnight, get extra rest before the trip, take a real nap if drowsiness sets in, and never push through severe drowsiness with caffeine alone.