When it comes to bizarre weather, megacryometeors are as bizarre as it gets. Sure, raining animals and invisible tornadoes are bizarre, but we have an idea what causes them and we typically have an idea that it is raining, even if it is raining something odd. Megacryometeors are impossible to predict, appear for no apparent reason out of clear skies, are capable of injuring people and their origins are completely unknown.
The best possible description of a megacryometeor is a huge chunk of hail appearing out of a clear blue sky. They have been known to cause property damage and small impact craters in the ground. These icy meteors can weigh between one and more than one hundred pounds. They are not meteors in the sense that they come from space -- as far as we know -- there is just no better name for them because they do not seem to originate from clouds and neither do meteors.
There are several theories out there that provide potential explanations for megacryometeors. One is a little gross, if you ever happen to be hit by a megacryometeor, but no worries, it has been proven wrong. For a long time, people thought that these ice balls might actually be waste from airplane toilets. Testing of megacryometeors shows that there is no evidence of human waste or toilet sanitation chemicals in them.
Another theory is that megacryometeors are ice chunks that forms on aircraft and then drop to the ground. The problem with this is that researcher and planetary geologist Jesus Martinez-Frias studied a bout of megacryometeors in Spain and found instances where planes were not known to be overhead at the time of the incident. There are also reports of megacryometeors from before there were aircraft.
Megacryometeors may also be simply forming high up in the atmosphere. There simply is no way to prove or disprove that, as there have only been roughly 50 reports of megacryometeors in the past 11 years. That slims down the risk of being hit with one -- thank goodness.