It’s raining cats & dogs.
What does that even mean? I looked it up and found from different sources pretty much the same thing. There is a theory (some say is not true) that a LONG time ago when it rained really hard cats and dogs would be found dead along the streets supposedly from falling off of roofs when trying to find shelter during the rain. Another theory is that dead cats & dogs were washed up from sewers during hard rainfalls. Either one is pretty disgusting. But they are just theories. Here is a link where you can read more:
The Library of Congress-Everyday Mysteries.
Read the full post here.