You may have seen an incredible video of what appeared to be snow covering the ground in Delaware County, but it was actually hail!
It is a sight that is quite unusual to see in this part of the country.
The hail came from a supercell thunderstorm, a rotating storm that actually caused a tornado just north of Wilmington.
There was so much cold air aloft that the tops of the thunderstorm were about 20 degrees below zero, which caused the excessive amount of hail to form.
So how does that happen?
Frozen water droplets are suspended by thunderstorm updrafts. Because this storm was spinning, even more hailstones are suspended.
Eventually, they fall out of the sky, and so much fell yesterday that it looked like snow.
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