Ah, yes... that moment when you're out hunting, lying on a shale outcrop on a VERY chilly morning, hunting Pennsylvanian fossils & wishing you had worn a heavier jacket than just a thin cotton hoodie...
... when suddenly you hear "tick... tick tick... tick..." and wonder "What's that noise?" ... then you realize it's from tiny bits of sleet starting to hit the ground around you.
It got worse fairly quickly, and I had to deal with a 7/10ths of a mile walk back to the car, across a dam, trying to carry my gear & keep my hood low enough across my face that I could still see, without getting nailed in the face by the rather sharp bits of ice raining down. They were at minimum 1/16th of a inch in diameter, and REALLY stung. Some were even painful through my sleeves!
This was NOT in the forecast!
(I wasn't alone in this misadventure, but am not naming the other person, unless said person wishes to ID themself.)