Wiktionary
hundred-year storm
alt. A storm of such force that it occurs only once every one hundred years approximately. n. A storm of such force that it occurs only once every one hundred years approximately.
Usage examples of "hundred-year storm".
The brine shrimp and the algae and a few other hardy aquatic forms would thrive until the waters drained and evaporated away, leaving fresh eggs and spores entombed in the sediment to await the next Hundred-Year Storm.
I found it difficult to believe that, with so many routes to follow, the runoff from even a hundred-year storm would rise as far as the midpoint of one of the larger arteries.
In what everybody agreed was a hundred-year storm, the poorest section of the state was devastated.