In Memphis, after a torrential downpour, it began to rain down snakes in one part of the city.  In a two block area surrounding Vance Street, there residents of Memphis experienced snake rain in 1877.  It was reported in a government periodical in January of 1877 called "Monthly Weather Review" and again the following month in a national magazine called "American Scientific."   The snakes were between 12 and 18 inches in length and were so thick in areas that they were described as being, "a mass of thread or yarn."  

References:

It's Raining Cats and Dogs by MrNussbaum.com

When Snakes Rained on Memphis, published in Memphis The City Magazine by Vance Lauderdale

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