I was on the way to work from lunch, in 2006 and had to sit through 3 cycles of traffic lights.    Why?   The temperature was 80+ degrees and I stop at the light.   Suddenly, it was like someone dropped you in the Antarctic.   I immediately close the moonroof and windows.   The guy next to me wasn't so "quick".   After 5 seconds, the heavens dropped hail stones the size of marbles.   You could NOT see in front of your car.   It was hailing like this for about 4 minutes.   No rain, just hail.  
The hail stops and you see the most wicked Cumulonimbus (Thunderhead) off to the East.   Rumor is, a tornado touched down in Detroit from the same storm.   Noone knows for sure, but the cold updraft was something I learned while studying Meteorology.    
Rip, next time you see a wall cloud, try not to gaze.   

    Good to see the Nelson family made it out ok though.   Prayers for the victims have been said.   
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