There's no "official" definition of what constitutes a day of heavy precipitation, but an inch of rain or melted snow is a reasonable threshold. On average, we get about ten such days per year, with more of those days in summer than in any other season because the atmosphere is so loaded with moisture. Autumn, with its tropical threat, is a distant second.

If we further define the watermark - no pun intended - to just those days with two inches or more - real supersoakers - the average is less than two days per year, and the dominance of summer is even stronger. In fact, summer has almost as many of these high precipitation days as the other three seasons combined. And August is the one summer month with the most.

In fact, if you take away September 16, 1999, the rainiest day in local recorded history thanks to the six plus inches dumped by Hurricane Floyd, the next three rainiest days all occurred in August. One of those was this date in 1873, when a whopping five plus inches of rain fell.