From 1774 to 1900, there were 17 recorded instances of snow falling in Florida.
During the 20th century, there were 20 instances.
Thus far in the 21st century, there have been 12 snowfalls.
Here's the arithmetic:
Line 1, about one snowfall every seven and one-half years.
Line 2, one every five years.
Line 3, one every year.
January 19, 1977 Miami saw its first snowfall. Snow fell as far south as Homestead.