https://twitter.com/#!/x/status/1822713717458620670
How does this occur?
Sometimes updrafts can force the rain water to such high altitudes that it freezes, and then once the ice balls form, it is heavy enough to where it crashes back down, and doesn't melt by the time it hits the ground.
An explanation is here: https://www.kvue.com/article/weather.../269-546665755