I haven't done this since I was a kid, but I thought we would try it again.  Also you can see it happen in slow motion, which is pretty comical.  Check out what happens!

The science behind it is that warmer water's molecules want to release energy faster than colder water.  When it's tossed in the air, the water droplets have a smaller surface area exposed to the frigid temperatures and freeze much faster.  Pretty neat!