People have used the phrase "It's Raining Cats and Dogs" for centuries, according to some accounts. Over time, several phrases have been introduced to describe a hard rain event, such as a thunderstorm as follows:

• Raining pitchforks
• Raining stair rods

None have caught on so well as raining cats and dogs. This popular weather folklore phrase was first referred to in 1651 in poems and in plays. Artists of the day had sometimes referred to animals that fell from the sky.

It was not until 1738 when Jonathan Swift published a satire of upper class conversation in his book “The Complete Collection of Genteel and Ingenious Conversation,” that raining cats and dogs became more of a popular term to use when referring to a particularly hard rain. Of particular interest are references to flooding, which may have lead to the phrase. Prolonged rain can produce flooding which lead to dead cats and dogs left in the streets.

According to the Library of Congress, the true origin of the phrase is unknown. Some popular ideas about the origin of the phrase include references to Norse and Greek mythology. Witches, which were associated with black cats, and the Norse god of storms, which was associated with dogs, may have been an early reference to storms. dogs” may refer to a storm with wind (dogs) and heavy rain (cats). Cata doxa, a Greek expression meaning “contrary to experience or belief” may have meant it is raining unusually hard.