rainstorm

Etymology

rain + storm

noun

1. A storm characterized by substantial, heavy rainfall.
   Philander went into the next room[…]and came back with a salt mackerel that dripped brine like a rainstorm. Then he put the coffee pot on the stove and rummaged out a loaf of dry bread and some hardtack. 1913, Joseph C. Lincoln, chapter 8, in Mr. Pratt's Patients
   To make matters worse, we pass through a torrential rainstorm, which makes window-gazing almost impossible, leaving me glad that the trip is less than 30 minutes duration. November 16 2022, Paul Bigland, “From rural branches to high-speed arteries”, in RAIL, number 970, page 55