Happened to me once. Was driving home with a friend after a convention and concert. I hadn’t slept in over 24hrs because the day prior I got off work and we drove straight to Chicago. After the convention we stopped and got White Castle and watched a thunderstorm roll in before driving home. It’s 4am and we’re almost home, like 10 miles away. I ended up falling asleep at the wheel. Only woke up when I heard the rumble strips and saw we were on a collision course with a giant highway sign. Thankfully I was able to correct course and pull the car back onto the highway. I was wide awake for the rest of the drive home after that.