“Boston suffered its worst flooding in 40 years”
Which means that at least 40 years ag0, and likely before that, and before that Boston suffered equal or greater flooding. Thus, not out of the “natural” realm of possibilities.
https://www.youtube.com/watch?v=udkGPcCP538
Old newscast of the Ash Wednesday storm of 1962. Great, dramatic news story - just the facts. (With a great voice and music to make it more dramatic).