I'll define "major rainstorm" as more than 50mm (2 inches) of rainfall in a single storm, or 25mm (1 inch) in an hour. I know that Europe doesn't get the "big and flashy" severe weather like hurricanes and big tornadoes, but what about just awfully big storms?
Around me, we've had some huge storms the past few days (not directly related to the hurricane down south but probably stemming from the same general weather conditions), including one that dropped 75mm (3 inches) of rain in about an hour and a half on a town not far from where I am. Storms like this aren't uncommon around here, we get 3 or 4 a year plus probably another dozen that are around half that. Central North Carolina actually gets more mm of rain a year than a lot of places with reputation as being very rainy, like Seattle or the UK (it just comes in a small number of massive deluges, versus constant drizzle.)
Seeing that big storm on the morning news made me think "man, I hope nobody was walking or biking to work when that fell," which then made me think "what do they do in the Netherlands (where, according to the stereotype, the people have bicycles instead of legs) when they get huge rain like this," which led to "do they get huge rain like this in Europe?" So, do you?