Snow is kinda rare in places and people do things like this. I did...
It was the great Christmas Snow of 2004 in SE Texas...and we got 9" of snow. My dad was in the hospital in Houston, fighting a terminal illness, and it just killed us that he couldn't watch his grandkids play in the snow. So on Christmas morning I made him a snowball...and kept it in the freezer for when he came home.
Dad passed in April of 2005...and I clung to that snowball...until Ike hit and knocked out power for a week.
Of the things I lost...I think I miss my snowball the most.
Perhaps the snowball just wanted to complete your task and escaped the only way it could; just imagine how happy your dad must be now, holding it carefully in his hands.